Reale, Viviana; Monechi, Simonetta (1991): New biostratigraphic data based on calcareous nannofossils of the Middle-Upper Jurassic interval in the Northwest Atlantic (Sites 534A and 105) and in the Umbria-Marche area. International Nannoplankton Association, The Hague, International, In: Young, J. R. (editor), International Nannoplankton Association; 4th conference; abstracts, 13 (2), 65-66, georefid:2006-060692