John and John Weldon Ankerberg, Encyclopedia of New Age Beliefs: The New Age Movement, Eugene OR, Harvest House Publishers, , 263 p. (ISBN978-1565071605, lire en ligne).
Martin Gardner, The Universe in a Handkerchief: Lewis Carroll's Mathematical Recreations, Games, Puzzles, and Word Plays, New York, Springer, , 61 p. (ISBN978-0387256412, lire en ligne).
Darrell P. Rowbottom, Popper's Critical Rationalism: A Philosophical Investigation, New York, Routledge, , 12 p. (ISBN978-0415992442, lire en ligne).