1. Amazon EC2, 2006. http://aws.amazon.com/ec2.
2. IBM SmartCloud Enterprise, 2011. http://www-935.ibm.com/services/us/en/cloud-enterprise/index.html.
3. IBM cloud computing from Wikipedia: 2012. http://en.wikipedia.org/wiki/IBM_cloud_computing.
4. IBM Smart Business Desktop Cloud, 2012. http://www-07.ibm.com/businesscenter/au/services/cloud_computing/smart_business_desktop_cloud.html.
5. R. Buyya, R. Ranjan, R.N. Calheiros, Modeling and simulation of scalable cloud computing environments and the cloudsim toolkit: challenges and opportunities, in: HPCS, 2009.