1. Albanesi, G.L., Hünicken, M.A. & Barnes, C.R., 1998. Bioestratigrafia, biofacies y taxonomia de conodontes de las secuencias ordovicicas del cerro Potrerillo, Precordillera Central de San Juan, R. Argentina. Academia Nacional de Ciencias, Córdoba, República Argentina, 249 pp.
2. Conodonts from the Fort Peña Formation (Middle Ordovician), Marathon Basin, Texas;Bradshaw L.E.;Journal of Paleontology,1969
3. Conodont studies;Branson E.B.;University of Missouri Studies,1933
4. Facies preference predicts extinction risk in Ordovician graptolites
5. The Lower Ordovician Fillmore Formation of western Utah: Storm-dominated sedimentation on a passive margin;Dattilo B.F.;Brigham Young University Geology Studies,1993