@book{bhlpg7836485, title = {Bulletin }, volume = {no.272 (1968)}, url = {https://www.biodiversitylibrary.org/page/7836485}, publisher = {G.P.O}, author = {United States National Museum }, year = {1968}, pages = {Page 137}, } @book{bhlpg12427820, title = {Fresh water sponges; a monograph }, url = {https://www.biodiversitylibrary.org/page/12427820}, publisher = {Academy of Natural Sciences}, author = {Academy of Natural Sciences of Philadelphia. }, year = {1887}, pages = {Page 252}, }