Énay, R., and M. K. Howarth. “The Upper Oxfordian and Lower Kimmeridgian Ammonite Genera Idoceras Burckhardt, 1906, and Subnebrodites Spath, 1925”. Paleontological Contributions, no. 17, Mar. 2017, pp. 1-3, doi:10.17161/1808.23377.