Authors Year Title
Gordon 1965 Carboniferous Cephalopods of Arkansas.
Professional Papers, U.S. Geological Survey, 460: 1-322, fig.1-96, pl.1-32; Washington. [imprint 1964].
Popov 1975 Ammonoidea (Ammonoidei). In: Paleontologicheskii Atlas kamennougol'nykh otlozhenii Urala. [In Russian].
Trudy VNIGRI 383: 111-130, pls.35-44, Leningrad (Nedra).
Ruzhencev & Bogoslovskaya 1971a Namiurskii etap v evoliutsii ammonodei. Rannenamiurskie ammonoidei.
Trudy Paleontologicheskogo Instituta Akademiya Nauk SSSR, 133: 1-382, fig.1-89, pl.1-40; Moskva.
Titus 2000 Late Mississippian (Arnsbergian Stage-E2 chronozone) ammonoid paleontology and biostratigraphy of the Antler foreland basin, California, Nevada, Utah.
Bulletin 131 Utah Geological Survey, 1-108, 51 text-figs., 17 tabls., 16 pls., Salt Lake City.