(Last updated Jan. 22, 2010)
| Brachiopods from the Lower Ordovician of Texas | Preston Cloud | Bulletin of the Museum of Comparative Zoology; v. 100, no. 5-6.; 1948 |
| Late Cambrian and Early Ordovician faunas from the Wilberns Formation of central Texas | Don Winston, and Harry Nicholls | Journal of Paleontology; January 1967; v. 41; no. 1; p. 66-96 |
| Nautiloids from the Gorman and Honeycut of Central Texas * | A. G. Unklesbay | Journal of Paleontology, Vol. 35, No. 2 (Mar., 1961), pp. 373-379 |
| New Echinoderms from the Early Ordovician of West Texas * | James Sprinkle and Gregory P. Wahlman | Journal of Paleontology, Vol. 68, No. 2 (Mar., 1994), pp. 324-338 |
| Pendent Graptolites of Arkansas, Oklahoma, and Texas * | Charles E. Decker | Journal of Paleontology, Vol. 18, No. 4 (Jul., 1944), pp. 378-386 |
| Revision of Middle Ordovician orthoceratacean nautiloids from Baltoscandia * | BJÖRN KRÖGER | Acta Palaeontologica Polonica 49 (1): 57–74, 2004 |