Best books to learn the "classical" approach for Black against the flank openings

Perhaps I should have said the word "minor" rather than "flank" in the title of this thread... I wanted to say "against flank openings, the English, and the Reti", but the title of this thread would be too long and not include all of the letters... therefore I simply left out the English and the Reti, but included them in my first post.  My bad, thanks for catching it, Lyudmil.

I am unable to say for sure, but my guess would be that Lyudmil_Tsvetkov was complaining about the way "flank" is generally used, and indeed he may have a point. As I have noted many times, nobody seems to be generally recognized as being in charge of chess terminology, and, consequently, the development of common usage seems to have been somewhat haphazard and not overly logical. Nevertheless, if the goal is to use a single word and have others think of the Reti and the English, my guess is that "flank" would be a better word choice than "minor". Yes, I do know about that book with "Minor" in the title, but it seems to be something of an anomaly. In view of the current frequency of Reti and English usage by over-2400 players, I suspect that many would not think of them as "minor". "Flank", on the other hand, has been used many times in connection with the openings that do not traditionally start with 1 e4 or 1d4. At least for over-2400 players, the Reti and the English are the most common openings in that category.