Hoehn, R. G. (1995). Science puzzlers!: 150 ready-to-use activities to make learning fun : grades 4-8. Center for Applied Research in Education.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रHoehn, Robert G. Science Puzzlers!: 150 Ready-to-use Activities to Make Learning Fun : Grades 4-8. West Nyack, N.Y: Center for Applied Research in Education, 1995.
एमएलए (9वां संस्करण) प्रशस्ति पत्रHoehn, Robert G. Science Puzzlers!: 150 Ready-to-use Activities to Make Learning Fun : Grades 4-8. Center for Applied Research in Education, 1995.
चेतावनी: ये उद्धरण हमेशा 100% सटीक नहीं हो सकते हैं.