H. H.  Godwin-Austen, ?On a Collection of Land-Shells made in Borneo by Mr. A. Everett, with Descriptions of supposed new Species. Part II. Zonitidae and Helicidae.?, Proceedings of the Zoological Society of London, pp. 22-47, 1891.

M. M.  Schepman, ?The Mollusca of the Dutch Scientific Borneo-Expedition?, Notes from the Leyden Museum, vol. 17, pp. 145-162, 1896.