The mathematician Walter Ledermann has dies. There has been a Times obituary and a better one in the Independent.
Ledermann was very influential in my undergraduate learning. I used his book on Group Theory to learn the subject and the series of books he edited, and in some cases wrote, called the Library of Mathematics was great. Each book was a pocket-sized summary of some subject such as mathematical analysis, multiple integrals or complex analysis. The books left out a lot of the clutter and so it was possible to see what was really important in the area.
Needless to say he was influential in my writing of How to Think Like a Mathematician.
