This book is another one of the ones that has been used extensively, honestly i dont know how it is still in great shape. Its got a good amount of time still and the great thing is that it is not filled with notes! There is one page which i took a picture of that is literally tapped on but that page is only the cover picture. Take a look at the pic to see what i mean. Its obviously not new but its one book that has a ton of info if this subject is what you are into or studying.