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1990 The Fourth Andean Council of Presidents, La Paz

1990 Visit of President Rodrigo Borja Cevallos of Ecuador

1990 Christmas, Rights of the Child

1990 Unification of Germany – International Stamp Exhibition “PHILATELIA ’90” – Berlin

1990 Unification of Germany

1990 The 700th Anniversary of the Swiss Confederacy

1990 The 400th Anniversary of the Larecaja District

1990 America UPAEP – Local Motifs

1990 The 500th Anniversary of the Discovery of America by Columbus, 1992

1990 The 100th Anniversary of the Cochabamba Social Club