Branger P. (2009) Buffevent (Deux-Sèvres), une nouvelle coupe de référence pour la base du Callovien // Nature entre Deux-Sèvres. No.2. P.52-58. pdf: http://rogov.zwz.ru/Branger,%202009_callovien-bathonien.pdf
This article provides new information concerning terminal Bathonian and basal Callovian in Submediterranean succession and their correlation with Subboreal zonal scale. Studies section characterized by mixed ammonite assemblage in the lower part of the Bullatus Zone, including subboreal (Kepplerites keppleri) and Submediterranean (Bullatomorphites, Macrocephalites, Paralcodia) taxa. New faunal horizon introduced for the top of the Middle Bathonian Bremeri Zone. This horizon characterized by Choffatia cf. uriniacensis.
Thanks to Patrick Branger for pdf