Engdahl, Sylvia [Louise](b. 1933). Defenders of the Flame. Eugene, OR: Ad Stellae, 2013.

Engdahl, Sylvia [Louise](b. 1933). Promise of the Flame. Eugene, OR: Ad Stellae, 2009.

Engdahl, Sylvia [Louise](b. 1933). Stewards of the Flame. Eugene, OR: BookSurge, 2007.

Engdahl, Sylvia [Louise](b. 1933). The Doors of the Universe. New York: Atheneum, 1981.

Engdahl, Sylvia [Louise](b. 1933). Beyond the Tomorrow Mountains. New York: Atheneum, 1973.

Engdahl, Sylvia [Louise](b. 1933). This Star Shall Abide. New York: Atheneum, 1972.

Engdahl, Sylvia [Louise](b. 1933). The Far Side of Evil. New York: Athenaeum, 1971.

Engdahl, Sylvia [Louise](b. 1933). Enchantress of the Stars. New York: Athenaeum, 1970.