@article {3287, title = {Offene {\"O}kosysteme f{\"u}r OER}, year = {2013}, pages = {28-30}, url = {http://www.uni-hamburg.de/eLearning/eCommunity/Hamburger_eLearning_Magazin/eLearningMagazin_11.pdf}, author = {Heinen, Richard and Michael Kerres and Ingo Blees and Rittberger, Marc} }