@article {BoutabaJISA12,
   author = {Boutaba, Raouf and Cheng, Lu and Zhang, Qi},
   title = {On Cloud computational models and the heterogeneity challenge},
   journal = {Journal of Internet Services and Applications},
   publisher = {Springer London},
   pages = {77-86},
   volume = {3},
   issue = {1},
  year = {2012}
}