Martins, António M. De Frias, Carlos P. Brito, and Thierry Backeljau. “Oxychilus (Drouetia) viridescens (Gastropoda: Pulmonata: Oxychilidae), a New Species from Santa Maria, Açores, and a Review of the Subgenus”. Zootaxa 3619, no. 3 (February 28, 2013): 343–368. Accessed April 19, 2025. https://mapress.com/zt/article/view/zootaxa.3619.3.5.