Reitlinger, E. A. (1950). ???????????? ????????????????????? ????????? ??????????? ????? ??????? ????????? (???????? ???. Fusulinid??) - Foraminifera of the Middle Carboniferous deposits of the central part of the Russian Platform (exclusive of family Fusulinidae). ???????? ???? ???? ????? ???-Academy of Sciences USSR Proceedings Insitute of Geological Sciences. 126: 1-128., available online at (http://www.ginras.ru/library/pdf/ign126_1950_reitlinger_carboniferous_forams.pdf) page(s): p. 16 pl. 2 fig. 15
