Spezzaferri, S.; Murero, D.; Premoli Silva, I. (1991): Paleoclimatic interpretations based on Oligocene planktonic foraminifera; a comparison between Hole 538A, DSDP Leg 77 (Gulf of Mexico) and Hole 709B, ODP Leg 115 (Indian Ocean). Societa Geologica Italiana, Rome, Italy, In: Cita, Maria Bianca (editor), Geology of the oceans, 44, 129-134, georefid:1994-052722