http://www.theleadenhallbuilding.com
http://www.skyscrapercenter.com/london/the-leadenhall-building/1194
http://www.ctbuh.org/LinkClick.aspx?fileticket=kkeAQ%2fHPwBU%3d&tabid=53&language=en-US
http://www.ctbuh.org/HighRiseInfo/TallestDatabase/Criteria/tabid/446/language/en-US/Default.aspx