Freitag, H. & Jäch, M.A. (2007)

Revision of the species of Hydraena Kugelann (Coleoptera: Hydraenidae) from Palawan and Busuanga, with descriptions of eleven new species, and redescription of Hydraena (Hydraenopsis) scabra d’Orchymont, 1925

. Zootaxa, 1431 (1), 1–44.