Rowson, B.; Herbert, D. G. (2016). The type species and circumscription of the species-rich Afrotropical snail genus Gulella L. Pfeiffer 1856, based on anatomical and mtDNA data (Mollusca: Eupulmonata: Streptaxidae). Archiv für Molluskenkunde. 145(1): 69-84.
The type species and circumscription of the species-rich Afrotropical snail genus Gulella L. Pfeiffer 1856, based on anatomical and mtDNA data (Mollusca: Eupulmonata: Streptaxidae)