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1952 The 100th Anniversary of Manizales

1952 Building of Post Offices WM: 4

1952 Colombian Doctors

1952 International Airmail – Local Motives

1952 Airmail – Local Motives

1951 Nationalization of Barranca Oilfields – Previous Issue Overprinted “REVERSION CONCESION MARES 25 Agosto 1951” WM: 4

1951 The 8th Anniversary of the Death of Guillermo Valencia, 1873-1943

1951 Airmail – Local Motives

1951 Airmail – Local Motives

1951 The 60th Anniversary of Colombian Society of Engineer