Helwerda, R. A., Wesselingh, F. P. and Williams, S. T. (2014) “On some Vetigastropoda (Mollusca, Gastropoda) from the Plio-Pleistocene of the Philippines with descriptions of three new species”, Zootaxa. Auckland, New Zealand, 3755(2), pp. 101–135. doi: 10.11646/zootaxa.3755.2.1.