This precise historical phonetics is essential for anyone interested in old French (phonetic point of view). The explanations are clear, although classified and properly treated (treatment of phonetic evolution by consonants, vowels, according to their place in the word ...). At the end of the book, there are even small cards that show an example phonetic evolution of certain words, from Latin to modern French; perfect to understand the method. Any phonetic study brings to this book: precisely and concisely are the hallmarks of this book. For those who wish to spend the CAPES or study the letters, here are indispensable in your library.