This is the 6th Edition of the "chess player's bible." Modern Chess Openings, 'MCO' was first published in 1911 by the British players Richard Clewin Griffith (1872–1955) and John Herbert White (1880–1920). Harry Golombek called it "the first scientific study of the openings in the twentieth century". MCO has continued to be updated throughout the 20th century and into the 21st, with fifteen editions from 1911 through 2008. Early editions were small enough to fit in a pocket (the first edition was 190 pages), but later editions grew and the fifteenth and most recent version is 768 pages. In 1977, Harry Golombek said "The work became popular at once and for over forty years was regarded as the main book on the openings throughout the world." The first three editions (1911, 1913, and 1916) were the work of Griffith and White, with an introduction by Henry Ernest Atkins. Editions through at least 1946 continued to be attributed to Griffith and White, with Philip Walsingham Sergeant and Maurice Edward Goldstein providing revisions starting with the fourth edition in 1925. In 1939, Reuben Fine became the first grandmaster to edit MCO. Walter Korn worked on the 7th-13th edition, assuming editorship with MCO-8 in 1952.