- E-bookThe Thirty-Six Strategies of Ancient ChinaStefan Verstappen
- E-bookDefense Against the PsychopathStefan Verstappen
- E-bookBlind Zen, Martial arts and Zen for the blind and vision impairedStefan Verstappen
- E-bookThe Little Warriors Street Safety Teachers GuideStefan Verstappen
- E-bookLittle Warriors Street Safety WorkbookStefan Verstappen