Keller, J. E. (1967). Alfonso X, el Sabio. Twayne Publishers.
Chicago Style (17th ed.) CitationKeller, John Esten. Alfonso X, El Sabio. New York: Twayne Publishers, 1967.
MLA (8th ed.) CitationKeller, John Esten. Alfonso X, El Sabio. Twayne Publishers, 1967.
Warning: These citations may not always be 100% accurate.