Mexico, 1914-15 "ES" Revoluntionary overprint covers, collection of 27 Revolutionary covers (Estado de Sonora) neatly mounted and in a binder, includes the beautiful overprint on 1903, 1908 and 1910 issues, covers are in great condition, including combinations with Coach Seals, U.S. stamps, Green Seals, Transitorios, etc. (no photo). Estimate  $400 - 600. $0