1. Adams, C. G. & Ager, D. V. (Eds) (1967): Aspects of Tethyan Biogeography. — Syst. Assn. Publ.7, 1–336.
2. Ager, D. V. (1967): Brachiopod Palaeoecology. — Earth. Sci. Rev.3, 157–179.
3. - (1971): Space and Time in brachiopod history. [In:] Middlemiss, Rawson & Newell (Eds.): Geol. J., spec. Issue4, 95–110.
4. Anderson, E. J. (1971): Environmental models in palaeozoic communities. — Lethaia,4, 287–302.
5. Anderson, E. J. &Makurath, J. H. (1973): Palaeoecology of Appalachian gypidulid brachiopods. — Palaeontology,16, 381–389, pls. 39–40.