Donald Greenspan is Professor of Mathematics at the University of Texas, where he received the Distinguished Research Award in 1983. An experienced lecturer, he has authored 200 papers and 14 books, many of them textbooks on computational mathematics. His assignments included positions at Harvard, Stanford, Berkeley and Princeton.Nigel Rees is a leading authority on the use of well-known phrases and sayings. As a broadcaster, he is best-known as the deviser and presenter of BBC Radio's Quote...Unquote.As an author, he has written many books devoted to quotations and aspects of the popular use of the English language, always emphasizing the humour in his subject.