India 1948 Gandhi Airmail cover to Czechoslovakia

India 1948 Gandhi 1½a brown ovpt “SERVICE” type O17, on Official cover from the Private Secretary to the Governor General of India to Dr. Mono Mohon Das in New Delhi, cancelled by “GOVERNOR GENERAL CAMP P.O. NEW DELHI 17 AUG 48” double ring cds. With New Delhi delivery of 18 Aug 48 on reverse. Extremely rare – 2011 RPSL certificate