Attacking the Flexible Sicilian
by Vassilios Kotronias and Semko Semkov, 404 pages
GM Vassilios Kotronias is ten-time champion of Greece and a famous theoretician. His peak rating so far was 2628 in 2008.
Semko Semkov played for Bulgaria in one Olympiad. He is a chess journalist and theoretician. He has authored The Most Flexible Sicilian, Kill K.I.D., Attacking the English/Reti, and other books.