Lowell R. Laudon, A. E. Hartwig, Dean L. Morgridge, John B. Omernik; Middle and Late Paleozoic stratigraphy, Alaska-Yukon border area between Yukon and Porcupine rivers. AAPG Bulletin ; 50 (9): 1868–1889. doi:
Graphic sections show detail of the Devonian Nation River, Mississippian Calico Bluff, and Permian Tahkandit Formations from localities near Eagle, Alaska. The Devonian age of the Nation River Formation, assigned from evidence presented by Churkin and Brabb (1965), is questioned, and three possible explanations of the stratigraphic relations are illustrated. A fauna of probable Early Pennsylvanian age is listed from the Calico Bluff Formation, and several faunal collections from the Tahkandit are of Permian age. Mississippian, Pennsylvanian, and Permian fauna were obtained from a section of unnamed rocks near the junction of the Salmontrout River with the Porcupine River.