Loeblich, A. R., Tappan, H. N., 1987: Foraminiferal genera and their classification. Van Nostrand, Reinhold Co. New York 1728 pp. Plate 214, Fig. 11-12: L. Carboniferous (Serpukhovian Substage), Donets Basin. 11, Holotype, x 70; 12, paratype, x 70 (from Brazhnikova and Vdovenko, 1983). courtesy of Michael Hesemann https://foraminifera.eu