@book{bhlpg31085669, title = {1997 IUCN red list of threatened plants }, volume = {1997}, url = {https://www.biodiversitylibrary.org/page/31085669}, publisher = {}, author = {}, year = {1997}, pages = {Page 315}, } @book{bhlpg40576391, title = {Contributions from the United States National Herbarium }, volume = {v.55 (2007)}, url = {https://www.biodiversitylibrary.org/page/40576391}, publisher = {Smithsonian Institution Press}, author = {United States. National Herbarium. }, year = {2007}, pages = {Page 331}, }