1. Appellöf, A.: Die Schalen vonSepia, Spirula undNautilus. Studien über den Bau und das Wachstum. — Kgl. Svenska Vetensk. Akad. Handl25, (7), 106 S., 3 Abb., 7 Taf., Stockholm 1893.
2. Birkelung, T.: Submicroscopic shell structures in early growth-stage of Maastrichtian ammonites (Saghalinites andScaphites). — Medd. dansk geol. Foren.,17, (1), 95–101, 3 Abb., 4 Taf., Kopenhagen 1967.
3. Birkelung, T. &Hansen, H. J.: Early shell growth and structures of the septa and the siphuncular tube in some Maastrichtian ammonites. — Medd. dansk geol. Foren.,18, 71–78, 7 Abb., 4 Taf., Kopenhagen 1968.
4. Druschtschiz, W. W. &Chiami, N.: Strojenje sept, stjenki protokoncha i natschalnich oborotow rakowini nekotorich rannjemjelowich ammonitow. — Paleont. žurn., 1970, (1), 35–47, 5 Abb., 1970
5. Erben, H. K.;Flajs, G. &Siehl, A.: Ammonoids: Early ontogeny of ultramicroscopical shell structure. — Nature,219 (5152), 396–398, 4 Abb., 1968.