Incoming cover from Guatemala sent by airmail franked with 1929 3c deep purple, 15c ultramarine and 1927 1c olive green TAX issue (SG 230, 234 & 223) tied by CORREO AEREO INTERNACIONAL GUATEMALA cancels dated 26 NOV 1930. Addressed to MERIDA, YUCATAN with fine strike of circular 'R.A.C. No. 4 R.M.' (Ruta Aerea Contratada - route no. 4 - Tejeria - Tapachula) airmail route marking applied in transit with MERIDA arrival cds on reverse.