I've found very interesting book on on Cold war plans of Warsaw Pact on South European Theater (Balkans, Turkish Straits, etc.). Great advantage of this book - it's written with a heavy reliance on documents from the archives of Warsaw Pact countries. And for the first time I've seen heavy use of recently declassified Soviet documents (from Ukrainian Military Archive in Kiev). The only drawback of the book - it's written in Russian Here’s a link to the author's web-site: https://warplans.