Skinner, J. W.; Wilde, G. L. (1965). Permian biostratigraphy and fusulinid faunas of the Shasta Lake area, northern California. The University of Kansas Paleontological Contributions, Protozoa. 6: 1-98., available online at (http://hdl.handle.net/1808/3813) page(s): p. 90 plate 52, figures 1 (holotype)-6