- Mythic Tales of the Americas (1985)
- Merlin: A Biography (2000)
- Who's Who in Celtic Mythology (2002)
- Who's Who in Asian Mythology (2003)
- Who's Who in African Mythology (2005)
- The Illustrated Encyclopedia of Celtic Mythology (2005)
- Who's Who in Native American Mythology (2006)
- The Illustrated Encyclopedia of Norse Mythology (2007)
- The Illustrated Encyclopedia of Egyptian Mythology (2008)
- The Illustrated Encyclopedia of Greek Mythology (2011)
- Who's Who in Roman Mythology (2012)
- The Illustrated Encyclopedia of Mayan Mythology (2013)
- The Illustrated Encyclopedia of Aztec Mythology (2014)
- The Illustrated Encyclopedia of Inca Mythology (2015)
Short Stories
- "The Sword in the Stone" (2002)
- "The Fisher King" (2003)
- "The Green Knight" (2004)
- "Sir Gawain and the Green Knight" (2005)
- "The Quest for the Holy Grail" (2006)
- "Robin Hood" (2007)
- "King Arthur" (2008)
- "The Knights of the Round Table" (2009)
- "The Legend of Beowulf" (2010)
- "The Mabinogion" (2011)
- "The Tain Bo Cuailnge" (2012)
- "The Táin Bó Cúailnge" (2013)
- "The Saga of the Volsungs" (2014)
- "The Poetic Edda" (2015)