Sawin, R. S., & West, R. R. (2005). Paleoecology of the Permian (Wolfcampian) Phylloid Alga Calcipatera from an In Situ Occurrence in Kansas, U.S.A. Current Research in Earth Sciences, 251, 1-14. https://doi.org/10.17161/cres.v0i251.11835