Loeblich, A. R., Tappan, H. N., 1987: Foraminiferal genera and their classification. Van Nostrand, Reinhold Co. New York 1728 pp. Plate 16, Fig. 4: Holocene, Arctic Ocean. Side view, x 28 (from Averintsev, 1911). courtesy of Michael Hesemann https://foraminifera.eu
