Loeblich, A. R., Tappan, H. N., 1987: Foraminiferal genera and their classification. Van Nostrand, Reinhold Co. New York 1728 pp. Plate 144, Figs. 1-3: U. Cretaceous. 1, Maastrichtian of Council Pit, Norwich, England, longitudinal section, x 32; U. Cretaceous, Germany, 2, 3, side and apertural views, x 39 (2, 3, from Loeblich and Tappan, 1964).
