Hi,
I wrote the essay with my own thoughts and experiences using these kind of software social networking tools,
however I did reference 5 other sites, but not necesarily took any information from them rather placed them there since that is where I read to find out more about them and they basically made me "aware" of some I did not know. For this it is best to have experienced these worlds like Second Life, I used it for about a year around 2006 and 2007, so I know what it is all about and have extensive personal experience with it, due to this assignment question and went and read about additional virtual worlds and read about the differences between them
Bye