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Marshall, Bruce A.; Hills, Simon F.K.; Vaux, Felix (2018). "A new species of Penion P. Fischer, 1884 from northern New Zealand (Mollusca: Neogastropoda: Buccinoidea)". Molluscan Research. 38 (4): 238–242. doi:10.1080/13235818.2017.1420398. S2CID90709310.