Summers,George J. (2005). Puzzles and teasers. Jaico Publishing House.
Dyfyniad Arddull ChicagoSummers,George J. Puzzles and Teasers. Mumbai: Jaico Publishing House, 2005.
Dyfyniad MLASummers,George J. Puzzles and Teasers. Jaico Publishing House, 2005.
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