21 books • 8 series
Book #1: Griddlers Logic Puzzles Advanced Vol. 1
Book #2: Griddlers Logic Puzzles Advanced Vol. 2
Book #2: Griddlers Logic Puzzles
Book #3: Griddlers Logic Puzzles
Book #28: Griddlers Logic Puzzles
Book #1: Griddlers Logic Puzzles
Book #1: Griddlers - Number Logic Puzzles
Book #1: Griddlers Logic Puzzles - Triddlers Color
Book #1: Griddlers - Word Search