@article{ERMS:SourceID:294149, author = {Graf, D.L.}, journal = {Proceedings of the Academy of Natural Sciences of Philadelphia}, title = {Palearctic freshwater mussel (Mollusca: Bivalvia: Unionoida) diversity and the comparative method as species concept}, url = {http://www.marbef.org/data/aphia.php?p=sourcedetails&id=294149}, year = {2007} }