Castro, Elizabeth (2005). "Creating a Web Page with HTML: Visual quick project guide," San Francisco, CA, USA: Peachpit Press, ISBN 032127847X, see , accessed 19 September 2015.
Souders, Steve (2007). "High Performance Web Sites: Essential Knowledge for Front-End Engineers," Sebastopol, CA, USA: O'Reilly Media, ISBN 0596550693, see , accessed 19 September 2015.
