Hernando, C., and I. Ribera. “Two New Terrestrial Species of Hydraena Kugelann from the Island of Bioko, Gulf of Guinea (Coleoptera: Hydraenidae)”. Zootaxa, vol. 4238, no. 2, Mar. 2017, pp. 281–286, doi:10.11646/zootaxa.4238.2.10.