「SET遊戲」 http://www.setgame.com/set/ http://www.nytimes.com/ref/crosswords/setpuzzle.html
「THAT A WAY」
http://www.puzzles.com/products/thataway.htm
「數字三重奏」 http://www.mathdb.org/competition/essay/0506/articles/JM2.pdf