J. & W. Chester, Ltd.
Founded in 1860s. Acquired by Wilhelm Hansen in 1960s. Now a division of Music Sales, Ltd.
Chester plate numbers were most often preceded by the letters J.W.C. or J. & W.C. until the acquistion by Hansen in the 1960s. Thereafter, the prefix CH #### is encountered. Post-1970 reprints of earlier works typically include the new CH prefix.