Katz, N. (2009). Zen and the art of crossword puzzles: A journey down and across. Adams media.
Chicago Style aipamenaKatz, Nikki. Zen and the Art of Crossword Puzzles: A Journey Down and Across. Avon: Adams media, 2009.
MLA aipamenaKatz, Nikki. Zen and the Art of Crossword Puzzles: A Journey Down and Across. Adams media, 2009.
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