@article {8243, title = {The genus Echinochloa in North America}, journal = {Rhodora}, volume = {23}, year = {1921}, month = {1921///}, pages = {49 - 65}, author = {K.M. Wiegand} } @article {8128, title = {Bijdrage tot de kennis der Nederlandsche Rumices}, journal = {Nederl. Kruidk. Arch.}, volume = {1921}, year = {1921}, month = {1921///}, pages = {167 - 228}, author = {B.H. Danser} }