After long and meticulous reading, underlineing, studying, contemplating on this last book that Stanislavski wanted to write but was published with the help post-mortem. He didn't see the light of day. But apart from the other two books- this book kind of recapitulates all the main subjects from the other two and adding a finalization of thought.
A very good guide to actors and actresses, anyone interested in pursuing to be an actor should ready the three books chronologically. Because only ready the first two- does a lot of the things mentioned on the third makes sense and molds its soul into a form, a body.
Lots of references were made on Stanislavsky's autobiographical "My Life in Art", after reading these 3 books (1- An Actor Prepares 2- Building a Character 3- Creating a Role), I want to read this book.
A good reference for all cinema or theatre actors/actresses interested in pursuing acting.