Loeblich, A. R., Tappan, H. N., 1987: Foraminiferal genera and their classification. Van Nostrand, Reinhold Co. New York 1728 pp. Plate 130, Figs. 9-14: U. Cretaceous (L. Turonian), Tajikistan. 9-11, Opposite sides and edge view of holotype, x 120; 12-14, opposite sides and edge of paratype showing produced circular aperture, x 120 (from V. I. Korchagin, 1964). courtesy of Michael Hesemann https://foraminifera.eu
