William James Sidis: The Man Who Spoke 25 Languages - History of Yesterday

And even created his own language

Who Was William James Sidis, The Smartest Person In The World?

Why did the most intelligent man in the world (William James Sidis) leave nothing relevant in the World of Mathematics or other disciplines? - Quora

25 Highest IQ's Throughout History

Sidis Archives

William James Sidis: the Tragic Story of the Smartest Person Ever Lived - Learning Mind

William James Sidis Biography

William James Sidis, the most intelligent being who ever lived, by Giuseppe Frisella

Who Is The Smartest Living Person In The World Today?

William James Sidis Biography

William James Sidis: the Tragic Story of the Smartest Person Ever Lived - Learning Mind

William James Sidis, horoscope for birth date 1 April 1898, born in New York, with Astrodatabank biography

Bookride: The most intelligent man in the world

Who Was William James Sidis, The Smartest Person In The World?