@book{westrich_paul_wildbienen_1990,  address = {Stuttgart, DEU},  edition = {2},  title = {Die {Wildbienen} {Baden}-{Württenbergs}. {Spezieller} {Teil}},  volume = {2},  isbn = {3-8001-3317-2},  language = {de},  publisher = {Ulmer},  author = {{Westrich, Paul}},  year = {1990}, }