Loeblich, A. R., Tappan, H. N., 1987: Foraminiferal genera and their classification. Van Nostrand, Reinhold Co. New York 1728 pp. Plate 254, Figs. 15-16: U. Permian, S. Ussuriysk district. 15, Sagittal section of lectotype, x 60; 16, sagittal section of paratype, x 60 (from Tumanskaya, 1953). courtesy of Michael Hesemann https://foraminifera.eu