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Parker, https://ppiiii.com William G. (2006). “The stratigraphic distribution of main fossil localities in Petrified Forest National Park, Arizona” (PDF). Axsmith, Brian J.; Ash, Sidney R. (2006). “Two uncommon fossil cones from the Upper Triassic Chinle Formation in Petrified Forest National Park, Arizona, and New Mexico”. Ash, Sidney R. (1989). “A catalog of Upper Triassic plant megafossils of the western United States by 1988” (PDF).

Kustatscher, Evelyn; Ash, hongkongtriad1 Sidney R.; Karasev, Eugeny; Pott, Christian; Vajda, prizma58.ru Vivi; Yu, slotsonline Jianxin; McLoughlin, Stephen (2018), https://888app7.com (what is it worth) Tanner, Lawrence H. (ed.), “Flora of the Late Triassic” (PDF), The Late Triassic World, Topics in Geobiology, vol. Sidney R. Ash & Geoffrey T. Creber (2000). “The Late Araucarioxylon arizonicum Timber of the Petrified Forest National Park, Arizona, USA”. Miller, Gary L.; Ash, Sidney R. (1988). “The oldest freshwater decapod crustacean, from the Triassic of Arizona” (PDF).

Miller, Charles N. (1968). “The Lepidophytic Affinities of the Genus Chinlea and Osmundites Walkeri”.