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Arkhipkin, Alexander I.; Bizikov, Vyacheslav A.; Fuchs, Dirk (2012). "Vestigial phragmocone in the gladius points to a deepwater origin of squid (Mollusca: Cephalopoda)". Deep Sea Research Part I: Oceanographic Research Papers. 61: 109–122. Bibcode:2012DSRI...61..109A. doi:10.1016/j.dsr.2011.11.010.
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Arkhipkin, Alexander I.; Bizikov, Vyacheslav A.; Fuchs, Dirk (2012). "Vestigial phragmocone in the gladius points to a deepwater origin of squid (Mollusca: Cephalopoda)". Deep Sea Research Part I: Oceanographic Research Papers. 61: 109–122. Bibcode:2012DSRI...61..109A. doi:10.1016/j.dsr.2011.11.010.
