Walter Warwick Sawyer (or W.W. Sawyer) was a mathematician, mathematics educator and author, who taught on several continents.https://en.wikipedia.org/wiki/Walter_...
Prelude to Mathematics
W. W. Sawyer
Mathematician's Delight
W.W. Sawyer
What Is Calculus About?
Concrete Approach to Abstract Algebra
A First Look at Numerical Functional Analysis (Dover Books on ...
Vision in Elementary Mathematics (Dover Books on Mathematics)
Path to Modern Mathematics
Introducing Mathematics, Vol. 1: Vision in Elementary Mathematics
The search for pattern (His Introducing mathematics, 3) (v. ...
Mathematics in Theory and Practice