@electronic{twitter.com,
   title       = {Twitter: What are you doing?}, 
   url         = {http://twitter.com/},
   biburl      = {https://puma.uni-kassel.de/url/1cc089548931c4fe0463e7a98ec6078e/benz},
   keywords    = {networking online service twitter},
   added-at    = {2011-02-04T16:09:09.000+0100},
   description = {Twitter is a service for friends, family, and co–workers to communicate and stay connected through the exchange of quick, frequent answers to one simple question: What are you doing?},
   interhash   = {1cc089548931c4fe0463e7a98ec6078e}, 
   intrahash   = {1cc089548931c4fe0463e7a98ec6078e}
}

@electronic{library20.ning.com,
   title       = {Library 2.0}, 
   url         = {http://library20.ning.com/},
   biburl      = {https://puma.uni-kassel.de/url/97198bea19618b73c469ddd43b3487c1/hotho},
   keywords    = {2.0 Community library networking social},
   added-at    = {2007-12-06T11:13:03.000+0100},
   description = {},
   interhash   = {97198bea19618b73c469ddd43b3487c1}, 
   intrahash   = {97198bea19618b73c469ddd43b3487c1}
}