100 Maddening Mindbending Puzzles, Logic problems, maths conundrums and word games, HarperCollins Publishers, David Wells, Rob Eastaway,Crosswords and word games,Puzzles and quizzes, logic;quizz;brain training;brain games;MENSA;GCHQ;Crossword;logic problems;Bletchley;smart games,, , United Kingdom, en-GBhttps://www.harpercollins.co.uklogic;quizz;brain training;brain games;MENSA;GCHQ;Crossword;logic problems;Bletchley;smart games, [BLURB],[CITY],,books, ebooks, biblet, Book2look