Branger P. (2007) Nouvelles données biostratigraphiques dans le Sinémurien du Poitou (France) // Nature entre Deux-Sèvres. n°1. P.18-22. pdf: http://rogov.zwz.ru/Branger,2007_sinemurien.pdf
Hitherto our knowledges about Sinemurian of Poitou were based upon poor preserved ammonite (Leptechioceras Meigen (Hug)), discovered at the mid of the XIX century. New record of other ammonite, belonging to Gleviceras subguibalianum, suggests presence of the Upper Sinemurian in this region.
PS. Thanks to Patrick Branger for pdf