 Will Shortz does not write the "Times" crossword himself; the puzzles are submitted to him by a wide variety of contributors.A full specification sheet listing the paper's requirements for crossword puzzle submission can be found online (see "External Links") or by writing to the paper.Aside from increasing in difficulty throughout the week, the Monday–Thursday puzzles and the Sunday puzzle always have a theme, some sort of connection between at least three long (usually Across) answers, such as a similar type of pun, letter substitution, or alteration in each entry.