BBC Sport - Athletics - Usain Bolt puts 400m mission on hold until after 2012
Sprint king Usain Bolt ponders switch to long jump, soccer | The Star
Bolt eyes Johnson's 400m record
Bolt cruises to world record in 100-meters
Will lightning Bolt strike thrice? Usain lining up Johnson's 400m world record | Daily Mail Online
Usain Bolt's Split Times and the Power of Calculus | Quanta Magazine
Usain Bolt aurait-il pu battre le record du monde du 400m ? – Anec'Sport
Christopher Taylor breaks Usain Bolt's 400M record at World Youth Championships 2015, Cali (COL) - YouTube
Usain Bolt delays plans to take on Michael Johnson's 400m world record | Usain Bolt | The Guardian
South Africa's Wayde Van Niekerk winner in Men's 400m breaking a new World record and Jamaica's Usain Bolt winner in Men's 100m during the Olympic Games RIO 2016, Athletics, on August 14,
Bolt Needs Little Urging to Crush His 200 World Record - The New York Times
Despite the rain, Bolt blasts 19.59sec in Lausanne – IAAF World Athletics Tour | NEWS | World Athletics
Usain Bolt: 400m (45.35) 2003 - YouTube
Usain Bolt wins gold, minus glitter | The Star
Rio Highlights: Usain Bolt Defends Crown; S. African Sets World 400 Record : The Torch : NPR
Bolt could go for 400m - Eurosport
Bolt, Jamaica smash world record in 400 relay – The Mercury News
Why is Usain Bolt retiring at the age of 31? - Quora
South African 400m World Record Holder Challenges Usain Bolt in 200m Dash