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- Course Hero http://www.coursehero.com/
- Fratfolder http://fratfolder.com/
- Rock My Midterm http://rockmymt.com/
- ScribD http://www.scribd.com/
- Notehall http://www.notehall.com/
- Koofers http://www.koofers.com/
- CampusBuddy http://www.campusbuddy.com/
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