Guthrie, J., & Preston, T. (2005). Improve your brain power: 400 games, puzzles, and teasers to unlock your mind. Reader's Digest.
Chicago Style aipamenaGuthrie, Jackie, and Tim Preston. Improve Your Brain Power: 400 Games, Puzzles, and Teasers to Unlock Your Mind. Pleasantville, N.Y: Reader's Digest, 2005.
MLA aipamenaGuthrie, Jackie, and Tim Preston. Improve Your Brain Power: 400 Games, Puzzles, and Teasers to Unlock Your Mind. Reader's Digest, 2005.
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