Martin Hepp Katharina Siorpaes Daniel Bachlechner 54-65 2007 11 IEEE Internet Comput. 5 https://doi.org/10.1109/MIC.2007.110 http://doi.ieeecomputersociety.org/10.1109/MIC.2007.110 https://www.wikidata.org/entity/Q66708568 db/journals/internet/internet11.html#HeppSB07