MacDougall, M.J., Tabor, N.J., Woodhead, J., Daoust, A.R. and Reisz,
R.R., 2017. The unique preservational environment of the Early
Permian (Cisuralian) fossiliferous cave deposits of the Richards Spur
locality, Oklahoma. Palaeogeography, Palaeoclimatology, Palaeoecology,
vol. 475, pp.1-11.
https://www.researchgate.net/profile/Mark_Macdougall2
https://www.researchgate.net/publication/313589380_The_unique_preservational_environment_of_the_Early_Permian_Cisuralian_fossiliferous_cave_deposits_of_the_Richards_Spur_locality_Oklahoma?ev=prf_high
http://www.sciencedirect.com/science/article/pii/S0031018217301669
Yours,
Paul H.