1. Synonymical notes on Coleoptera of the United States, with descriptions of new species, from the MSS. of the late Dr. C. Zimmermann. Edited by John L. LeConte, M.D.;Zimmermann;Trans. Am. ent. Soc.,1869
2. The water beetles of Florida;Young;Univ. Fla. Publ. biol. Sci. Ser.,1954
3. Sphaeridini inhabiting Boreal America;Winters;Bull. Brooklyn ent. Soc.,1944
4. Key to the subtribe Helocharae Orchym. (Coleoptera-Hydrophilidae) of Boreal America;Winters;Pan-Pacif. Ent.,1927
5. Catalogue des Coléoptères aquatiques des familles des Dryopidae, Georyssidae, Cyathoceridae, Heteroceridae et Hydrophilidae;Zaitsev;Horae Soc. ent. rossicae,1908