48 Studies by Ferling for All Saxophones by Marcel Mule. Alphonse Leduc, 1946, SS, 30 pages. In addition to editing the 48 studies by Ferling for oboe, Professor Mule has written an additional 12 studies in major and minor keys. (Ferling did not include the enharmonic keys of C flat major, A flat minor, etc. in his work.)