Edgar Payne wrote a book called Composition of Outdoor Painting - first printed in 1941. Now you might not be an outdoor painter, but he has plenty to say about painting in general. The book is divided into three main chapters which serve to act as binders for groups of similar information.
Chapter 1 deals with ones approach to art. He covers such subjects as talent versus genius, originality, knowledge, discipline, and direct and remote influences one ones art work, as well as other topics.
Chapter 2 is more extensive and focuses on selection and composition. In this he covers a great deal of information, from mistakes in composing, and errors in arrangement, to perspective and values.
Chapter 3 then takes a look at different types of compositions. The principles he discusses, can be applied generally to many different types of painting - not only landscapes. If you are a self taught painter and not had any , or little formal instruction, then this is a book full of hidden gems and I think you will find it very useful. I have been painting for many years, and still found useful tips in it.
There is a link to the book from the top picture, it is fairly expensive, but well worth the investment in my opinion.