@techreport{RehfeldtFranzKoch2020, author = {Daniel Rehfeldt and Henriette Franz and Thorsten Koch}, title = {Optimal Connected Subgraphs: Formulations and Algorithms}, institution = {ZIB}, address = {Takustr. 7, 14195 Berlin}, number = {20-23}, language = {eng}, year = {2020} }