additional sourceNikolaeva, V. M. (1978). A revision of the subfamily Koellikerinae (Trematoda, Didymozoidae). Biologiia Moria, Kiev. 45: 65–71. (In Russian).[details]
new combination referenceAriola, V. (1906). Monostoma filicolle Rudolphi e Distoma okeni Kölliker. Zoologischer Anzeiger. 30 (6): 185–186. page(s): 186 [details]