Georgescu & Abramovich 2008. Taxonomic revision and phylogenetic classification of the Late Cretaceous (Upper Santonian-Maastrichtian) serial planktonic foraminifera (Family Heterohelicidae Cushman, 1927) with peripheral test wall flexure. Revista Espanola de Micropaleontologia, 40(1-2), Enero-Agosto 2008: 97-114