↑ Vyse, Stuart A. (2000). Believing in Magic: The Psychology of Superstition. Oxford, England: Oxford University Press. pp. 19–22. ISBN978-0-1951-3634-0.
↑ For discussion, see for example Georges, Robert A. & Jones, Michael Owen. 1995. Folkloristics: An Introduction, p. 122. Indiana University Press. ISBN0253329345.