1969 Airmail – The 50th Anniversary of 1st Colombian Airmail Flight
1969 Airmail – The 50th Anniversary of 1st Colombian Airmail Flight
Colombia
1969 Airmail – The 50th Anniversary of 1st Colombian Airmail Flight
1969 Airmail – The 50th Anniversary of 1st Colombian Airmail Flight
1969 Airmail – The 200th Anniversary of the Birth of Alexander von Humboldt
1969 Airmail – The 200th Anniversary of the Birth of Alexander von Humboldt
1969 Airmail – The 20th Anniversary of University of the Andes
1969 Airmail – The 20th Anniversary of University of the Andes
1969 Airmail – The 25th Anniversary of Inter-American Agricultural Sciences Institute
1969 Airmail – The 25th Anniversary of Inter-American Agricultural Sciences Institute
1969 The 25th Anniversary of Inter-American Agricultural Sciences Institute
1969 The 25th Anniversary of Inter-American Agricultural Sciences Institute
1968 The 100th Anniversary of First Antioquia Stamps and 7th National Stamp Exhibition – Medellin, Colombia
1968 The 100th Anniversary of First Antioquia Stamps and 7th National Stamp Exhibition – Medellin, Colombia
1968 The 100th Anniversary of First Antioquia Stamps and 7th National Stamp Exhibition – Medellin, Colombia
1968 The 100th Anniversary of First Antioquia Stamps and 7th National Stamp Exhibition – Medellin, Colombia
1968 Airmail – The 1st Congress for Electronic Data Processing and 100th Anniversary of National University, Bogota
1968 Airmail – The 1st Congress for Electronic Data Processing and 100th Anniversary of National University, Bogota
1968 The 100th Anniversary of National University
1968 The 100th Anniversary of National University