The English designer Hardy Amies, who passed away in 2003, was so far as I know the first important menswear designer. His book, ABC of Men's Fashion, was originally published in 1964, just as top down men's fashion was to disappear for twenty years in favor of street fashions.
Re-issued this month, ABC should be of interest to any man that appreciates classic dressing. Organized as a series of alphabetized definitions, it's a combination of forecasts that didn't happen - Amies believed that the next step for men would be high closing four button jackets and that boots would replace shoes - and useful thoughts on color, contrast, late day dress and other things you may not have thought about before.
For example, Amies points out that a 13 ounce mohair makes a great travel suit for all but the hottest destinations as it doesn't wrinkle and holds a crease as if it was made of metal. To that he adds that being relaxed on holiday should not mean that we walk around other people's cities dressed as if we were at a sea side resort. "Correct dressing is only another form of good manners, and good manners are only another form of mental comfort."