Mcadams, N.E., Adrain, J.M. & Karim, T.S. (2018)

The pliomerid trilobite Ibexaspis and related new genera, with species from the Early Ordovician (Floian; Tulean, Blackhillsian) of the Great Basin, western USA

. Zootaxa, 4525 (1), 1–152.