A third collection of proofs without words (PWWs) which will aid teachers of high school and college-level students.

Roger B. Nelsen was born in Chicago, Illinois. He received his BA in mathematics from DePauw University, Indiana in 1964 and his PhD in mathematics from Duke University, North Carolina in 1969. Nelson was elected to Phi Beta Kappa and Sigma Xi, and taught mathematics and statistics at Lewis and Clark College, Portland for forty years before his retirement in 2009. His previous books include Proofs without Words (1993), An Introduction to Copulas (1999, 2nd edition 2006), Proofs without Words II (2000), Math Made Visual (with Claudi Alsina, 2006), When Less Is More (with Claudi Alsina, 2009), Charming Proofs (with Claudi Alsina, 2010), The Calculus Collection (with Caren Diefenderfer, 2010), Icons of Mathematics (with Claudi Alsina, 2011), College Calculus (with Michael Boardman, 2015), A Mathematical Space Odyssey (with Claudi Alsina, 2015) and Cameos for Calculus (2015).