1931. SOME ANGLES IN THE PROBLEM OF BIRD MIGRATION. Auk 48: 22—32.
(23) Gross, A. O.
1927. THE SNOWY OWL MIGRATION OF 1926-27. Auk 44: 479-493, illus.
(24) Harrison, T. H.
1931. ON THE NORMAL FLIGHT SPEEDS OF BIRDS. Brit. Birds 25: 86-96.
(25) Lincoln, F. C.
1917. BOHEMIAN WAXWING (BOMBYCILLA GARRULA) IN COLORADO. Auk 34: 341.
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1922. TRAPPING DUCKS FOR BANDING PURPOSES: WITH AN ACCOUNT OF THE RESULTS OBTAINED FROM ONE WATERFOWL STATION. Auk 39: 322-334, illus.
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