@article{RAMS:SourceID:39038, abstract = {all Hydrozoa names introduced in this work have been entered in the WoRMS database [some few may be missing]}, author = {Haeckel, E.}, doi = {10.5962/bhl.title.46856}, journal = {Denkschriften der Medicinisch-Naturwissenschaftlichen Gesellschaft zu Jena }, title = {Das System der Medusen. Erster Teil einer Monographie der Medusen}, url = {https://www.biodiversitylibrary.org/page/32605578}, year = {1879} }