Abbott, M. L. (1968). Lycopsid stems and roots and sphenopsid fructifications and stems from the Upper Freeport coal of southeastern Ohio. Paleontological Research Inst.
Chicago-Zitierstil (17. Ausg.)Abbott, Maxine L. Lycopsid Stems and Roots and Sphenopsid Fructifications and Stems from the Upper Freeport Coal of Southeastern Ohio. Ithaca, NY: Paleontological Research Inst, 1968.
MLA-Zitierstil (9. Ausg.)Abbott, Maxine L. Lycopsid Stems and Roots and Sphenopsid Fructifications and Stems from the Upper Freeport Coal of Southeastern Ohio. Paleontological Research Inst, 1968.
Achtung: Diese Zitate sind unter Umständen nicht zu 100% korrekt.