1. Chesbrough, H.W.: Open Innovation: The New Imperative for Creating and Profiting from Technology. Harvard Business Press (2003)
2. Speidel, K.-P.: Problem-Description in Open Problem-Solving. How to overcome Cognitive and Psychological Roadblocks. In: Sloane, P. (ed.) A Guide to Open Innovation and Crowdsourcing. Advice from Leading Experts. KoganPage, London (2011)
3. Lecture Notes in Computer Science;M. Stankovic,2011
4. Jeppesen, L.B., Lakhani, K.R.: Marginality and Problem Solving Effectiveness in Broadcast Research. Organization Science 20 (2009)
5. Sigurbjörnsson, B., van Zwol, R.: Flickr tag recommendation based on collective knowledge. In: Proceeding of the 17th International Conference on World Wide Web, WWW 2008, p. 327. ACM Press, New York (2008), doi:10.1145/1367497.1367542