Cushman, J. A. & Stevenson, F. V. 1948. A Miocene foraminiferal fauna from Ecuador. Cushman Lab.Foram.Research Contr. 24 (3): 50-68.
Cushman, J. A., et al. 1949. Quinault Pliocene foraminifera from western Washington. Bulletin of the Oregon Department of Geology Min. Industries. no. 36