Iakovleva and Kulkova, 2001
From dinoflaj3
Iakovleva, A.I. and Kulkova, I.A., 2001: Paleocene-Eocene dinoflagellate cysts and continental palynomorphs of the Pur Downstream Basin (northwestern Siberia): biostratigraphical and paleoenvironmental implications. Revista Española de Micropaleontologia, v.33, p.1-33.