TY - JOUR A1 - Ullah, Ayat A1 - Saqib, Shahab E. A1 - Kächele, Harald T1 - Determinants of Farmers’ Awareness and Adoption of Extension Recommended Wheat Varieties in the Rainfed Areas of Pakistan JF - Sustainability N2 - Scientific evidence suggests that there is room for eradicating poverty and hunger by increasing food production through the adoption of modern agricultural practices by farmers. This study aimed, first, to explore the relationship between the farmers’ awareness and adoption of improved wheat varieties. Second, it aimed to find the key factors that govern the farmers’ awareness and adoption of extension-recommended innovations in the rainfed cropping system of the Khyber Pakhtunkhwa, Pakistan. Data were collected from 395 respondents. A binary logit model was used to analyze the effect of the farmers’ socioeconomic and farm-specific characteristics on their awareness and adoption of the extension-suggested wheat varieties. Moreover, qualitative data from 40 key informants were collected for in-depth analysis. The results show a strong association between the farmers’ awareness of a technology (improved wheat varieties) and its adoption. The results of the logit model show that their extension contacts, income from agriculture, and access to credit positively affected the farmers’ awareness, whereas their education and household sizes negatively affected their awareness. Moreover, the factors that positively influenced the farmers’ decision to adopt the technology included the extension contact, the confidence in the extension, the risk-bearing attitude, and the credit access, whereas the household size and education negatively affected it. The results of the key informant interviews reveal that the high incidence of poverty, the low soil fertility, the farmers’ inability to make effective decisions, the lack of accurate weather predictability in the rainfed farming system, the lack of government interest, and the asymmetric information in the inputs markets contributed to the farmers’ low levels of awareness and to their poor adoption of improved agricultural technologies. These results indicate that any intervention aimed at the awareness and adoption by farmers of improved technologies, such as new wheat varieties, should recognize the heterogeneity in the farmers’ socioeconomic and farm-specific characteristics. KW - farmers’ awareness KW - technology adoption KW - improved wheat varieties KW - socioeconomic and farm-specific characteristics Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:eb1-opus-3496 SN - 2071-1050 VL - 14 IS - 6 PB - MDPI ER - TY - JOUR A1 - Ullah, Ayat A1 - Mahmood, Nasir A1 - Zeb, Alam A1 - Kächele, Harald T1 - Factors Determining Farmers’ Access to and Sources of Credit: Evidence from the Rain-Fed Zone of Pakistan JF - Agriculture N2 - This study investigates the factors that affect farmers’ access to agricultural credit and its role in adopting improved agricultural technologies in the rain-fed zone of Khyber Pakhtunkhwa (KP), Pakistan. Using logistic models, we assess and compare the relative role of farmers’ socioeconomic attributes in their access to credit and adoption strategies. The results indicate a moderate positive association between farmers’ access to agricultural credit and their adoption of improved agricultural technologies. The binary logit model’s results indicate that farmers with a large-sized farm, high farm income, better access to information, and large physical asset ownership showed a positive influence on credit access. However, farming experience showed a negative effect on farmers’ access to agricultural credit. Regarding farmers’ credit sources, this study found that asset-rich farmers with more farming experience and better access to information relied more on banks than on input providers and informal credit sources. Similarly, older farmers with more education, larger farm sizes and high farm income were more likely to have borrowed from input providers than banks. We conclude that the role of the effective provision of information on credit and agricultural technology is imperative and requires separate policies that are specifically aimed at different groups of farmers with different socioeconomic and farm-related characteristics. KW - agricultural credit KW - adoption of agricultural technologies KW - rain-fed zone KW - Khyber Pakhtunkhwa KW - socioeconomic attributes Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:eb1-opus-3419 SN - 2077-0472 VL - 10 IS - 12 PB - MDPI ER - TY - JOUR A1 - Biland, Mazhar A1 - Zeb, Alam A1 - Ullah, Ayat A1 - Kächele, Harald T1 - Why Do Households Depend on the Forest for Income? Analysis of Factors Influencing Households’ Decision-Making Behaviors JF - Sustainability N2 - Using survey information of 150 randomly selected households across 21 villages of the forest-rich district of Swat, Pakistan, this study assessed households’ decision-making behaviors in depending on income from nearby forested land using socio-economic attributes. The evidence from the study may aid in making the existing policies be better targeted toward families that depend on the forest for income. Descriptive statistics and econometric techniques such as logit and tobit were used to analyze the data. Respondent households obtained the highest share of their income from off-farm activities (37%) and least from forest activities (16%). Fuelwood constitutes the biggest share (66%) of forest income, followed by medical plants (20%) and fodder (13%). We found that households with more physical assets, more family members working in off-farm jobs, and households earning more income from off-farm jobs were significantly and negatively associated with households’ decision to depend on forest income and total income obtained. We also found that households with less distance to the market and membership to joint forest management committees (JFMCs) were significantly and negatively associated with households’ total income obtained. However, household size was significantly and positively related to households’ decision of forest dependency. The study recommends the creation of off-farm opportunities and inclusion of local people in the management of forests through establishment of JFMCs, particularly for large and poor families. KW - decision-making behavior KW - socio-economic attributes KW - forest income dependency KW - total income obtained Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:eb1-opus-3441 SN - 2071-1050 VL - 13 IS - 16 PB - MDPI ER - TY - JOUR A1 - Mahmood, Nasir A1 - Arshad, Muhammad A1 - Kächele, Harald A1 - Shahzad, Muhammad Faisal A1 - Ullah, Ayat A1 - Mueller, Klaus T1 - Fatalism, Climate Resiliency Training and Farmers’ Adaptation Responses: Implications for Sustainable Rainfed-Wheat Production in Pakistan JF - Sustainability N2 - Climate change is a severe threat to the agricultural sector in general and to rainfed farming in particular. The aim of this study was to investigate the factors that can potentially affect the adaptation process against climate change. This study focused on wheat farmers and farming systems in the rainfed agroecological zone of Pakistan. Farmers’ data related to climate change fatalism, the availability of climate-specific extension services, socioeconomic and institutional variables, and farm characteristics were collected. A logit model to assess farmers’ decisions to adopt an adaptation measure and a multinomial logit model to assess their choice of various adaptation measures were used. The results showed that fatalistic farmers were unlikely to implement climate change adaptation measures. The variables related to the climate-specific extension services, including farmers’ participation in training on climate-resilient crop farming and the availability of mobile communication-based advisory services, had highly significant and positive impacts on farmers’ decisions and their choice of adaptation measures. Input market access and tractor ownership also had positive and significant impacts on farmers’ decisions to adapt and their choice of adaptation measures. This study highlights the need to improve rainfed-wheat farmers’ education levels to change their fatalistic attitudes towards climate change. Furthermore, government action is needed to provide climate-specific extension services to ensure sustainable production levels that will ultimately lead to food and livelihood security under a changing climate. KW - fatalism KW - climate-specific extension service KW - climate-resilient farming KW - rainfed farming KW - adaptation Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:eb1-opus-3338 SN - 2071-1050 VL - 12 IS - 4 PB - MDPI ER - TY - JOUR A1 - Ullah, Ayat A1 - Zeb, Alam A1 - Saqib, Shahab E. A1 - Kächele, Harald T1 - Landscape co-management and livelihood sustainability: Lessons learned from the billion trees afforestation project in Pakistan JF - Land Use Policy KW - Billion Trees Afforestation Project KW - Landscape co-management participation KW - Livelihood improvement Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:eb1-opus-7407 SN - 1873-5754 IS - 115 PB - Elsevier ER - TY - JOUR A1 - Ullah, Ayat A1 - Zeb, Alam A1 - Saqib, Shahab E. A1 - Kächele, Harald T1 - Constraints to agroforestry diffusion under the Billion Trees Afforestation Project (BTAP), Pakistan: policy recommendations for 10-BTAP JF - Environmental Science and Pollution Research N2 - Effective agroforestry diffusion under the newly started 10-Billion Trees Afforestation Project (10-BTAP) needs a thorough understanding of the policy and implementation shortfalls of the already completed BTAP. This study examines the factors that affected the diffusion of the agroforestry in the Hindu-Kush Himalayan (HKH) region of Pakistan under BTAP. The data were gathered through in-depth interviews with Village Development Committee (VDC) members, Forest Department (FD) officials, and local farmers. Important factors positively affecting agroforestry diffusion included locations of crop fields on the river sides, community dependency on firewood, and market value of agroforestry timber. The logistic regression model shows that household head’s age, access to information, and area under cropland positively affected household level adoption of agroforestry under BTAP; forest cover was negatively related. In-depth interviews show that key barriers to FD in diffusion of agroforestry included provision of false information by farmers to monitoring teams, non-availability of extension staff, lack of communication among project staff and community, as well as a lack of sufficient budget for activities. Primary barriers to community adoption of agroforestry included no participation of VDCs in planning and monitoring of agroforestry programs, lack of plant need assessments on the part of the project staff, poor quality of plants distributed by FD, farmers’ poor know-how of plantations, lack of trust among community and project staff, as well as the waste of plants by farming community. Thus, this study recommends that policy-makers and project designers should consider these factors when planning agroforestry diffusion under 10-BTAP to improve its success. KW - Agroforestry diffusion; 10-Billion Trees Afforestation Project; Policy and extension; Hindu-Kush Himalayan; Village Development Committees; Planning and monitoring Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:eb1-opus-7419 IS - 29 SP - 68757 EP - 68775 PB - Springer Nature ER - TY - JOUR A1 - Ullah, Ayat A1 - Mishra, Ashok K. A1 - Bavorova, Miroslava A1 - Kächele, Harald T1 - The effect of COVID-19 pandemic on market integration: Evidence from vegetable farmers in Pakistan JF - International Journal of Disaster Risk Reduction N2 - The COVID-19 pandemic exposed the agriculture sector and farming communities to unprecedented risks. This study investigates the impact of the pandemic, identifying the suggestions of community elders for effective resilience via in-depth interviews (IDIs) and Focus Group Discussions (FGDs). We also examine determinants of vegetable farmers' inputs and outputs market participation using a binary logit model. The findings reveal poor business owners’ support, difficulties accessing inputs and outputs markets, non-availability/shortage of inputs recommended by extension services, and poor access to mechanizations. Labor shortages, lack of access to agricultural credit, and lack of information on innovations and markets are also barriers to market integration of farming communities in Pakistan. Results of the logit model show that farming experience and support from market owners drive the participation of both the inputs and outputs market. Similarly, ownership of personal vehicles and the availability of farm machinery drive the participation of farmers in outputs markets. Various strategies are suggested to mitigate the risks of the Covid-19 pandemic, including the establishment of inputs and outputs markets, strategies for transportation, access to information, and farm machinery at the local level. KW - Agriculture sector; Farming communities; Coronavirus; Markets integration Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:eb1-opus-7430 SN - 2212-4209 IS - 80 PB - Elsevier ER - TY - JOUR A1 - Ullah, Ayat A1 - Arshad, Muhammad A1 - Kächele, Harald A1 - Zeb, Alam A1 - Mahmood, Nasir A1 - Müller, Klaus T1 - Socio-economic analysis of farmers facing asymmetric information in inputs markets: evidence from the rainfed zone of Pakistan JF - Technology in Society N2 - Information asymmetry plays an important role in the non-adoption of modern agricultural inputs like improved seeds, pesticides and fertilizers etc. Therefore, this study investigated the role of farmers’ socio-economic attributes and farm level characteristics in avoiding asymmetry of information in agricultural input markets (i.e. exaggerated prices and low quality). The approach captures the farm level heterogeneity and complexity that may help the authorities in strengthening existing market regulations to control price and quality disparities. We analysed 395 randomly selected farm households using multinomial logit model. We found that farmers with large landholding size are less likely to face quality and more likely to face price information asymmetry. Farmers with higher education, more physical assets and better access to other sources of information are less likely to face both quality and price information asymmetry. Borrowers as compared to purchasers are more likely to face information asymmetry on prices of agricultural inputs. Non-adopters of improved agricultural technologies are more suspicious of information asymmetry than adopters. The paper thus provides evidence that the socio-economic dynamics of information asymmetry can have an important influence on wide spread adoption of technology. Paying more attention to farm level heterogeneity and complexity would help to develop general market management plan and improve the adoption of technology by farmers. Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:eb1-opus-7235 SN - 1879-3274 VL - 63 IS - 101405 PB - Elsevier ER - TY - JOUR A1 - Ullah, Ayat A1 - Arshad, Muhammad A1 - Kächele, Harald A1 - Khan, Ayesha A1 - Mahmood, Nasir A1 - Mülle, Klaus T1 - Information asymmetry, input markets, adoption of innovations and agricultural land use in Khyber Pakhtunkhwa, Pakistan JF - Land Use Policy N2 - This paper presents empirical evidence on the effects of information asymmetry in input markets on the adoption of innovations and agricultural land use in rainfed districts of Khyber Pakhtunkhwa, Pakistan. Farmers’ input market integration may contribute to innovation and adoption among farmers, which may in turn positively influence the sustainable use of agricultural land. To examine this hypothesis, we conducted a study of farmers and input providers to assess the potential constraints on quality inputs, prices, and extension information. We used a multistage random sampling technique to collect data from 395 respondents. We then compared differences among adopters and non-adopters using the Mann-Whitney U test and Mood’s median test. Our results indicate that there is a significant difference between the adopters and non-adopters when considering their perceptions of asymmetric market information. Non-adopters are suspicious of exaggerated prices, the non-availability of price lists, adulteration of agricultural inputs, unbalanced input weight and the supply of low-quality alternate commodities (e.g., fertilizers and pesticides) in place of the recommended commodities in the markets. Our results call for the reformulation and implementation of appropriate policies to ensure transparent and equal information sharing among farmers engaged in input markets and for the provision of timely and quality inputs assured by regulatory checks and price checks. Free availability of information on innovations and appropriate oversight over markets appear not only to motivate farmers to adopt agricultural technologies but also to influence more sustainable land use practices. Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:eb1-opus-7240 SN - 0264-8377 VL - 90 PB - Elsevier ER - TY - JOUR A1 - Mahmood, Nasir A1 - Arshad, Muhammad A1 - Kächele, Harald A1 - Ullah, Ayat A1 - Müller, Klaus T1 - Economic efficiency of rainfed wheat farmers under changing climate: evidence from Pakistan JF - Environmental Science and Pollution Research N2 - Rainfed wheat farming directly depends upon climatic indicators and is mostly at the mercy of climatic extremes. This study analyzed the relationship between the economic efficiency of rainfed wheat farmers and indicators of climate variability in Pakistan employing a two-stage methodological framework. We used farm household level crop input-output and management data and secondary data on climate. In the first stage, a stochastic production frontier (SPF) approach was used to calculate economic efficiency. Then, in the second stage, the calculated economic efficiency scores were regressed against the temperature threshold, temperature anomaly, and total rainfall, in addition to socioeconomic, institutional, and farm variables, using OLS and quantile regression models. The results showed that temperature anomaly and the number of days when temperatures exceed 30 °C have negative and significant impacts on the economic efficiency of rainfed wheat farmers. Total rainfall showed positive and significant impacts across both OLS and quantile regression models. Further, we modeled a novel and very important variable in the context of rainfed wheat production in Pakistan, that is, farmers’ participation in trainings in climate-resilient crop farming. This variable showed a positive and highly significant impact on economic efficiency of wheat farmers across all regression models. Our findings call for important policy implications, including developing up-to-date climate resilient adaptation strategies that are particularly focused on rainfed wheat farming. Establishing strong linkages between extension departments and rainfed wheat farmers could help sustain and improve the efficiency of rainfed wheat farmers and hence food and livelihood security. KW - Climate variability; Economic efficiency; Rainfed wheat; Stochastic production frontier; Quantile regression; Climate resilient crop farming Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:eb1-opus-7287 SN - 1614-7499 IS - 27 SP - 34453 EP - 34467 PB - Springer Nature ER - TY - JOUR A1 - Ullah, Ayat A1 - Sam, Anu Susan A1 - Sathyan, Archana Raghava A1 - Mahmood, Nasir A1 - Zeb, Alam A1 - Kächele, Harald T1 - Role of local communities in forest landscape restoration: Key lessons from the Billion Trees Afforestation Project, Pakistan JF - Science of The Total Environment N2 - The Billion Trees Afforestation Project (BTAP) was launched in the Khyber Pakhtunkhwa (KP) province of Pakistan to conserve existing forests and to increase the area under forest cover. It also aimed to restore environmental conditions, promote rural livelihoods and reduce poverty. To improve the effectiveness of afforestation projects, it is essential to know the role of various factors and their impacts on community participation in landscape restoration. However, these factors and their impacts remain unexplored for the BTAP. This study identifies the factors that influenced rural household participation in the BTAP in Pakistan. The data were collected from participants and nonparticipants in the BTAP as well as from various officials. We employed both qualitative and quantitative methods to analyze the data. The results of the focus group discussions and the professional evaluation of the BTAP revealed that participant farmers enjoyed all the benefits of the project at the individual and community levels. However, the project provided only partial benefits to nonparticipant farmers at both levels. The household-level results showed that age, income from forest resources, a friendly relationship with forest department staff, a risk-bearing attitude and membership or involvement in village development committee activities had positive and significant effects on farmer participation, while disputes over land and forest resources, household size and experience with/dependence on livestock farming had negative and significant impacts on farmer participation in the BTAP. Our results suggest that policymakers and project designers should pay more attention to the factors that hindered farmer participation in the BTAP. The participation of landless and disadvantaged groups in the 10-BTAP should be increased to ensure equal and widespread benefits for all users and to ensure a win-win situation of sustainable management of the forest, the environment and livelihood opportunities for all types of forest users. KW - Farmer participation; Sustainable management; Forest, environment and livelihood opportunities Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:eb1-opus-7326 SN - 1879-1026 IS - 772 PB - Elsevier ER - TY - JOUR A1 - Ullah, Ayat A1 - Zeb, Alam A1 - Liu, Jinlong A1 - Mahmood, Nasir A1 - Kächele, Harald T1 - Transhumant pastoralist knowledge of infectious diseases and adoption of alternative land use strategies in the Hindu-Kush Himalayan (HKH) region of Pakistan JF - Land Use Policy N2 - Pastoralists’ awareness of infectious disease outbreaks depends on their socioeconomic characteristics and considerably affects their land use strategies. This study aimed to identify the factors that affect transhumant communities’ awareness of recently emerged Coronavirus Disease 2019 (COVID-19) in humans and foot and mouth disease (FMD) in animals. This study also investigated the key factors that govern the adoption of alternative land use strategies by nonmigrating transhumants to avoid seasonal migration in the Hindu-Kush Himalayan (HKH) region of Pakistan. To link the awareness of disease spread to the adoption of alternative land use strategies, a focus group discussion and a socioeconomic survey were conducted in the study area. A total of 300 households were randomly selected from a nonmigrating transhumant community. The results of the binary logit model showed that landholding size, good relationships with extension field staff, and extension contact were positively related, whereas household education was negatively related to pastoralists’ awareness of infectious disease outbreaks. In the case of adopting alternative strategies to avoid future long-distance migration, our model showed that pastoralists’ awareness of infectious disease outbreaks significantly and positively affected pastoralists’ adoption of these strategies. The other variables that were positively associated with the pastoralists’ adoption of these strategies included good relationships with extension field staff, household size and primary dependence on pastoral-based livelihood, whereas the education level of the head of the household, lack of financial resources and disputes over agricultural lands/forests were negatively associated with the pastoralists’ adoption of these strategies. We conclude that to avoid infectious disease spread and promote adoption of alternative strategies, the government should pay attention to creating awareness among transhumant communities. Communicating the latest scientific research on infectious disease outbreaks and effective control measures that are translated in an understandable (pictographic) manner could be an effective policy intervention. Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:eb1-opus-7338 SN - 1873-5754 PB - Elsevier ER - TY - JOUR A1 - Kandel, Giri Prasad A1 - Bavorova, Miroslava A1 - Ullah, Ayat A1 - Kächele, Harald A1 - Pradhan, Prajal T1 - Building resilience to climate change: Examining the impact of agro-ecological zones and social groups on sustainable development JF - Sustainable Development N2 - Nepal is one of the most vulnerable countries to climate change, which is negatively affecting agricultural production and food security. However, the role of agro-ecological zones and social groups in climate change adaptation (CCA) and its impact on smallholder farmers in Nepal remains unexplored. To fill this gap, this study aimed to identify the effect of agro-ecological zones and social groups on smallholder farmers' adaptation to climate change using the multivariate probit model. Multistage sampling was used to collect data from 400 households in three agro-ecological zones of Nepal. These zones were highland (mountainous region), midland (hilly region) and lowland (terai/plain region). The results of our study showed that farmers in the Mountain region are more likely to adopt off-farm activities and temporary migration as a CCA strategy than those in the Terai/plain agro-ecological zone. In the Terai/Plain, farmers mainly adopt small-scale irrigation and agroforestry. In terms of social groups, the Brahmin group was more likely to adopt new crop varieties and small-scale irrigation than the Sudra group. The Sudra farmers preferred temporary migration and off-farm activities more than the Brahmins. Our study shows that policies to promote the adoption of CCA strategies need to take into account location and social group differences in order to improve the adaptive capacity of the most vulnerable farmers. Mountain and Sudra farmers need support to adapt to climate change and sustain agriculture. KW - agro-ecological zones KW - climate change KW - multivariate probit model KW - social groups KW - sustainable development Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:eb1-opus-8226 SN - 0968-0802 VL - 31 IS - 5 SP - 3796 EP - 3810 PB - Wiley ER - TY - JOUR A1 - Ullah, Ayat A1 - Zeb, Alam A1 - Saqib, Shahab E. A1 - Kächele, Harald T1 - Constraints to agroforestry diffusion under the Billion Trees Afforestation Project (BTAP), Pakistan: policy recommendations for 10-BTAP JF - Environmental Science and Pollution Research N2 - Abstract Effective agroforestry diffusion under the newly started 10-Billion Trees Afforestation Project (10-BTAP) needs a thorough understanding of the policy and implementation shortfalls of the already completed BTAP. This study examines the factors that affected the diffusion of the agroforestry in the Hindu-Kush Himalayan (HKH) region of Pakistan under BTAP. The data were gathered through in-depth interviews with Village Development Committee (VDC) members, Forest Department (FD) officials, and local farmers. Important factors positively affecting agroforestry diffusion included locations of crop fields on the river sides, community dependency on firewood, and market value of agroforestry timber. The logistic regression model shows that household head’s age, access to information, and area under cropland positively affected household level adoption of agroforestry under BTAP; forest cover was negatively related. In-depth interviews show that key barriers to FD in diffusion of agroforestry included provision of false information by farmers to monitoring teams, non-availability of extension staff, lack of communication among project staff and community, as well as a lack of sufficient budget for activities. Primary barriers to community adoption of agroforestry included no participation of VDCs in planning and monitoring of agroforestry programs, lack of plant need assessments on the part of the project staff, poor quality of plants distributed by FD, farmers’ poor know-how of plantations, lack of trust among community and project staff, as well as the waste of plants by farming community. Thus, this study recommends that policy-makers and project designers should consider these factors when planning agroforestry diffusion under 10-BTAP to improve its success. KW - - KW - Agroforestry diffusion KW - 10-Billion Trees Afforestation Project KW - Policy and extension KW - Hindu-Kush Himalayan KW - Village Development Committees KW - Planning and monitoring KW - Medical and Health Sciences Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:eb1-opus-9271 SN - 0944-1344 SN - 1614-7499 VL - 29 IS - 45 SP - 68757 EP - 68775 PB - Springer Berlin Heidelberg ER -