Slocum, Jerry and Jack Botermans. Puzzles, Old and New: How to Make and Solve Them. De Meern, The Netherlands: Plenary Publications International in association with the Craft and Folk Art Museum, Los Angeles, 1986.

Slocum, Jerry and Jack Botermans. Puzzles, Old and New: How to Make and Solve Them. De Meern, The Netherlands: Plenary Publications International in association with the Craft and Folk Art Museum, Los Angeles, 1986.