References
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- T. Annemann, The Book Without a Name, Max Holden, New York, 1931.
- A. Benjamin, Double Birthday Magic Squares, M-U-M (The Magazine for the Society of American Magicians) (August 2006) 68–69.
- A. Benjamin and M. Shermer, Secrets of Mental Math: The Mathemagician's Guide to Lightning Calculation and Amazing Math Tricks, Random House, New York, 2006.
- H. Lorayne, The Magic Book, 2nd ed., Putnam, New York, 1977.
- J. E. Ward III, Vector Spaces of Magic Squares, Math. Mag. 53 (1980) 108–111.