The Middle Game of Go
Published 1971 by Ishi Press. It consists of four very detailed game analyses of games by the author, Sakata Eio, based on booklets prepared by a Japanese go magazine.
See also David Carlton's review.
These are middle game analyses, the openings having been discussed in Modern Joseki and Fuseki.
This book launched the idea of middlegame joseki in the occidental literature, which was something of a mixed blessing.
This was supposed to be volume 1 of a series, but no more volumes were published.
Some content is discussed at BQM5
--- BramGo (4k):
This book is packed with diagrams. Each variation has a short title and about 3 lines of text per diagram. Useful book, do not expect to read it out in just a couple of days. It's a hard one and I needed a lot of motivation to read through this book.