S. R. Kruk et al. (2007)  implemented a social bookmarking system called Social Semantic Collaborative Filtering (SSCF). The goal of the SSCF is to enhance individual bookmarks with shared knowledge of the community. It also presents how digital libraries can be combined with social semantic information sources and it exemplifies how these techniques can improve e-Learning. Digital Libraries and other open courses can leverage their potential with the collaborative architectures. Learners can use it to exchange information, and express and synthetize knowledge e-Learning environments. It also makes use of the social bookmarking, web semantics and ontology services in other to organize and classify knowledge.
About this paper, I like the how it states the benefits of this e-Learning systems for companies and institutions and also the benefits web collaboration to boost learning. Additionally, the idea of using social bookmarking to classify educational content is pretty interesting.
 I. Hamburg, “eLearning 2.0 and Social, Practice-Oriented Communities to Improve Knowledge in Companies”, 2010 Fifth International Conference on Internet and Web Applications and Services, pp. 411-416, 2010.