Cephalopod
Shevyrev A.A. 2005. The Cephalopod macrosystem: a historical review, the present state of knowledge, and unsolved problems: 1. Major features and overall classification of cephalopod molluscs. Paleontological Journal. 39: 606-614. Translated from Paleontologicheskii Zhurnal #6, 2005, 33-42.