SCADTA: 1923 Switzerland: Registered cover from Zürich to Bogota and back to Swi
SCADTA
1923 Switzerland: Registered cover from Zürich to Bogota and back to Switzerland, franked by Swiss 50c. airmail stamp tied "SCHWEIZERISCHE LUFTPOST/27.VII.23" and with scarce usage of SCADTA Swiss Consular hand overprinted "S" in violet on 1921 5c. and 15c. tied in red on arrival in Barranquilla, and with...