http://www.wikipedia.org/
http://www.urbandictionary.com/
(Aguilar qtd. in MacGillivary & Curwen, 2007).
Tagging as a social literacy practice (Laurie MacGillivary, Margaret Sauceda Curwen)
http://onlinelibrary.wiley.com/doi/10.1111/jaal.2007.50.issue-5/issuetoc
http://www.tandfonline.com/doi/abs/10.1080/14753630500472059#preview