Ridge, M., & Billington, R. A. (1969). America's frontier story: A documentary history of westward expansion. Holt, Rinehart and Winston.
芝加哥风格引文Ridge, Martin, 与 Ray Allen Billington. America's Frontier Story: A Documentary History of Westward Expansion. New York: Holt, Rinehart and Winston, 1969.
MLA引文Ridge, Martin, 与 Ray Allen Billington. America's Frontier Story: A Documentary History of Westward Expansion. Holt, Rinehart and Winston, 1969.
警告：这些引文格式不一定是100％准确.