Ridge, M., & Billington, R. A. (1969). America's frontier story: A documentary history of westward expansion. Holt.
Chicago Style (17th ed.) CitationRidge, Martin, and Ray Allen Billington. America's Frontier Story: A Documentary History of Westward Expansion. New York: Holt, 1969.
MLA (9th ed.) CitationRidge, Martin, and Ray Allen Billington. America's Frontier Story: A Documentary History of Westward Expansion. Holt, 1969.
Warning: These citations may not always be 100% accurate.