@inproceedings{BugeScharfBecker2001, author = {Hans-Gerhard Buge and Holger Scharf and Roland Becker}, title = {Soil samples prepared for a proficiency testing scheme operated by BAM}, booktitle = {Biological and environmental reference materials (Fresenius' journal of analytical chemistry 370,2/3)}, editor = {T. Gills}, volume = {370}, number = {2-3}, pages = {174}, year = {2001}, }