
 BERNOULLI. The Columbia Encyclopedia: Sixth Edition. 2000 (Site not responding. Last check: ) 
  One of the chief developers both of the ordinary calculus and of the calculus of variations, he was the first to use the word integral in solving Leibniz’s problem of the isochronous curve. 
  He was succeeded at Basel by his brother, Johann, Jean, or John Bernoulli, 1667–1748, who earlier had been professor at Gröningen and who was famous for his work in the field of integral and exponential calculus and was also a founder of the calculus of variations. 
  His son, Daniel Bernoulli, 1700–1782, was a mathematician, physicist, and physician and has often been called the first mathematical physicist. 
 www.bartleby.com /aol/65/be/BernoulFam.html (289 words) 
