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L'Oiseau et la Revue francaise d'ornithologie - Société ornithologique de France. (Société ornithologique de France, 1972)

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Les oiseaux de la province de Que´bec - Dionne, C.-E. (Charles-Eusèbe), 1846 -1925 (Dussault & Proulx, 1906)

Les oiseaux de la Suisse (Catalogue des oiseaux de la Suisse de V. Fatio et Th. Studer) élaboré par ordre du Département fédéral de l'intérieur (Inspection des forêts, chasse et pêche) - Fatio, Victor, 1838 -1906 (1901)

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Oldman River Dam ... raptor mitigation program - Alberta. Alberta Environment. (Govt. of the Province of Alberta, Dept. of Public Works, Supply and Services, 1990)

Oldman River Dam ... raptor mitigation program - Alberta. Alberta Environment. (Govt. of the Province of Alberta, Dept. of Public Works, Supply and Services, 1992)

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The oölogist (J.M. Wade, 1877)

The oölogist (J.M. Wade, 1878)

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The Oölogist for the student of birds, their nests and eggs - Lattin, Frank H. (Frank H. Lattin, 1889)

The Oölogist for the student of birds, their nests and eggs - Lattin, Frank H. (Frank H. Lattin, 1891)

The Oölogist for the student of birds, their nests and eggs - Lattin, Frank H. (Frank H. Lattin, 1893)

The Oölogist for the student of birds, their nests and eggs - Lattin, Frank H. (Frank H. Lattin, 1894)

The Oölogist for the student of birds, their nests and eggs - Lattin, Frank H. (Frank H. Lattin, 1910)

The Oölogist for the student of birds, their nests and eggs - Lattin, Frank H. (Frank H. Lattin, 1912)

The Oölogist for the student of birds, their nests and eggs - Lattin, Frank H. (Frank H. Lattin, 1913)

The Oölogist for the student of birds, their nests and eggs - Lattin, Frank H. (Frank H. Lattin, 1914)

The Oölogist for the student of birds, their nests and eggs - Lattin, Frank H. (Frank H. Lattin, 1915)

The Oölogist for the student of birds, their nests and eggs - Lattin, Frank H. (Frank H. Lattin, 1918)

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Opinions and declarations rendered by the International Commission on Zoological Nomenclature - International Commission on Zoological Nomenclature (Printed by order of the International Trust for Zoological Nomenclature, 1955)

Opinions and declarations rendered by the International Commission on Zoological Nomenclature - International Commission on Zoological Nomenclature (Printed by order of the International Trust for Zoological Nomenclature, 1956)

Opinions and declarations rendered by the International Commission on Zoological Nomenclature - International Commission on Zoological Nomenclature (Printed by order of the International Trust for Zoological Nomenclature, 1939)

Opinions and declarations rendered by the International Commission on Zoological Nomenclature - International Commission on Zoological Nomenclature (Printed by order of the International Trust for Zoological Nomenclature, 1957)

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Ornis - International Ornithological Committee. (Carl Gerold's Sohn, 1886)

Ornis - International Ornithological Committee. (Carl Gerold's Sohn, 1887)

Ornis - International Ornithological Committee. (Carl Gerold's Sohn, 1888)

Ornis - International Ornithological Committee. (Carl Gerold's Sohn, 1889)