Ellis L. Yochelson and Charles E. Mason. 1986. A Chondrophorine Coelenterate from the Borden Formation (Lower Mississippian) of Kentucky, Journal of Paleontology, Vol. 60, No. 5 (Sep., 1986), pp. 1025-1028 [1]
peerj.com
Bruce S. Lieberman et al. 2017. Disc-shaped fossils resembling porpitids or eldonids from the early Cambrian (Series 2: Stage 4) of western U.S.A., PeerJ, [2]
