Walther, F. & Hausdorf, B. (2018). Case 3777 – Clausilia index Mousson, 1863, Clausilia semilamellata Mousson, 1863, Clausilia derasa Mousson, 1863 (Gastropoda, Stylommatophora, Clausiliidae): proposed conservation by suppression of the senior synonyms, Clausilia unilamellata Mousson, 1856, Clausilia multilamellata Mousson, 1856 and Clausilia firmata Mousson, 1856.
The Bulletin of Zoological Nomenclature. 75(1), 237-240, (31 December 2018).