Ron Campbell is a good reference text though some parts are extremely out of date. Equally Birch and Bramson is extremely out of date -although it may have been revised the style is very old-fashioned. Suggest you go for some of the more modern texts and books such as the Pooleys Air Presentations Pre-flight Briefings with Instructor Notes which come with overhead projector slides. Any FIC school worth its salt should be using this sort of material now not just relying on books written 30 years ago.