Classic book, out of date point of view
Girdlestone's analysis of the Mozart piano concerti was a classic in its time, and I used it for a project when I was in college back in 1971. Newer scholarship and points of view about 18th century performance practice have made his attitudes and point of view very dated...to borrow from another author writing about a similar subject, the viewpoint looks at Mozart through the fog of Beethoven and the rest of the 19th century, which is very inappropriate. If this had cost e a lot of money I'd be disappointed that I bought it now, but since it was inexpensive, even though it is an original printing and is in very good condition, I am glad to add it to my library.