Quinnild, Clayton L; Hugh E. Cosby (1958). "Relics of Climax Vegetation on Two Mesas in Western North Dakota". Ecology. 39 (1). Ecological Society of America: 29–32. doi:10.2307/1929963. JSTOR1929963.
jstor.org
Quinnild, Clayton L; Hugh E. Cosby (1958). "Relics of Climax Vegetation on Two Mesas in Western North Dakota". Ecology. 39 (1). Ecological Society of America: 29–32. doi:10.2307/1929963. JSTOR1929963.