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1977 Birds of the Galapagos Islands

1977 Airmail – The 40th Anniversary of the Death of Jose Peralta, Writer

1977 The 40th Anniversary of the Death of Jose Peralta, Writer

1977 Airmail – The 3rd Bolivarian Pneumological Seminar

1977 Airmail – Beatification of Brother Hermano Miguel

1977 Airmail – Meeting of the Presidents of Colombia and Ecuador –

1977 Airmail – Meeting of the Presidents of Colombia and Ecuador – Fluorescent Paper

1977 Airmail – The 50th Anniversary of Guayaquil Rotary Club

1977 Airmail – The 50th Anniversary of Guayaquil Rotary Club

1977 The 50th Anniversary of Guayaquil Rotary Club