Donald J Sobol - Fiction - 2004 - 422 pages
Quick mysteries are presented for the reader to solve, with solutions printed upside down at end of each mystery.
Donald J. Sobol - Juvenile Fiction - 1981 - 117 pages
Twelve-year-old Angie, while tracking a gang of teenage thieves to help her sister who is a police officer, becomes dangerously involved with counterfeiters.
Donald J. Sobol - Juvenile Fiction - 1975 - 96 pages
The solutions to ten mysteries solved by Leroy "Encyclopedia" Brown are given in a separate section challenging the reader to match wits with the ten-year-old mastermind of ...