Researchr is a web site for finding, collecting, sharing, and reviewing scientific publications, for researchers by researchers.
Sign up for an account to create a profile with publication list, tag and review your related work, and share bibliographies with your co-authors.
Margaret Mazzolini, Sarah Maddison. Sage, guide or ghost? The effect of instructor intervention on student participation in online discussion forums. Computers & Education, 40(3):237-253, 2003. [doi]