It is an amazing and very important book.
It is not a book of transcriptions, but it does have some transcriptions and partial transcriptions like 'Music of the Ottoman Court' by W.
Feldman.
The book discusses the manuscripts, music and composers.
There are plates of some of the original manuscripts (including one from 15th cent) at the back of the book.
Kyriakos Kalaitzidis has done an excellent job!