Singleness of purpose is one of the chief essentials for success in life no matter what may be one's aim.
John Davison Rockefeller Sr. (July 8, 1839 – May 23, 1937) was an American oil industry business magnate and philanthropist. He is widely considered the wealthiest American of all time, and the richest person in modern history.
Enjoy the best John D. Rockefeller picture quotes.
Read more about John D. Rockefeller on Wikipedia.