From UFOs to the curse of King Tut, Mystery Library examines those strange, often unbelievable or unexplainable events that have fascinated people through the ages. Every book includes primary sources, a bibliography for further reading, a complete list of works consulted, a thorough index and numerous photographs.
Kallen has written more than 350 nonfiction books for children and young adults. His books have covered a wide arc of human history, culture, and science. Kallen is also an accomplished singer-songwriter and guitarist in San Diego, California