Helwerda, R.A. 2015.

Acteonidae, Bullinidae and Ringiculidae (Gastropoda: Heterobranchia) from the Plio-Pleistocene of the Philippines

. Zootaxa. 3990, 2 (Jul. 2015), 197–220. DOI:https://doi.org/10.11646/zootaxa.3990.2.2.