Loeblich, A. R., Tappan, H. N., 1987: Foraminiferal genera and their classification. Van Nostrand, Reinhold Co. New York 1728 pp. Plate 272, Figs. 12-14: U. Carboniferous (Moscovian), USSR. 12, 14, Axial section of holotype, x 20, and enlarged, x 45; 13, axial section of paratype, x 20 (from Rauzer-Chernousova et al., 1951). courtesy of Michael Hesemann https://foraminifera.eu
