Wada T., 1999: Number of bird species breeding in parks of Osaka City. 11 pp. 

 Walasz K., 1990: Experimental investigations on the behavioural differences between urban and forest Blackbirds. 37 pp. [80922] Acta zoologica cracoviensia 33/12: 235-271.

 Walluschek-Wallfeld H., 1996: Erster Brutnachweis des Gänsesägers (Mergus merganser L.) für die Steiermark (Aves). 4 pp. 

 Walters M., 1991: Prosobonia ellisi, an extinct species of sandpiper from Moorea, Society Islands. 10 pp. (in English). Bolletino del Museo regionale di Scienze Naturali – Torino 9(1): 217-226.

 Wasilewski J., 1990: Dynamics of the abundance and consumption of birds of prey in the Niepolomice Forest. 41 pp. [80923] Acta zoologica cracoviensia 33/10: 173-213.

 Watson G. E., Amerson A. B., 1967: Instructions for collecting bird parasites. 12 pp. 

 Wetmore A., 1915: A peculiarity in the growth of the tail feathers of the Giant Hornbill (Rhinoplax vigil). 4 pp. 

 Wetmore A., 1919: Bones of birds collected by Theodoor de Booy from kitchen midden deposits in the Islands of St. Thomas and St. Croix. 11 pp. 

 Wetmore A., 1919: On the anatomy of Nyctibius with notes on allied birds. 10 pp. 

 Wetmore A., 1925: Fossil birds from southeastern Arizona. 18 pp. 

 Wetmore A., 1930: A systematic classification for the birds of the world. 8 pp. 

 Wetmore A., 1932: Birds collected in Cuba and Haiti by the Parish-Smithsonian Expedition of 1930. 40 pp. 

 Wetmore A., 1936: Two new species of hawks from the Miocene of Nebraska. 6 pp. 

 Wetmore A., 1937: Observations on the birds of West Virginia. 41 pp. 

 Wetmore A., 1938: A Miocene booby and other records from the Calvert formation of Maryland. 5 pp. 

 Wetmore A., 1938: Another fossil owl from the Eocene of Wyoming. 3 pp. 

 Wetmore A., 1939: Notes on the birds of Tennessee. 69 pp. 

 Wetmore A., 1940: Notes on the birds of Kentucky. 46 pp. 

 Wetmore A., 1941: Notes on birds of the Guatemalan highlands. 59 pp. 

 Wetmore A., 1944: A collection of birds from northern Guanacaste Costa Rica. 56 pp. 

 Wetmore A., Lincoln F. C., 1933: Additional notes on the birds of Haiti and the Dominican Republic. 68 pp. 

 Wiltowski J., 1972: Distribution and abundance of the hazel hen, Tetrastes bonasia (Linnaeus, 1758) (Aves) in southern Poland in 1966. 11 pp. [AVE 241] [English version of the paper published in 1968 in Acta zoologica cracoviensia 13/11: 265-276 – see cat. no. AZC 1311 (Wiltowski J., 1968).] Acta zoologica cracoviensia. 13(11): 101-112-

 Worthy T. H., Boles W. E., 2011: Australlus, a new genus for Gallinula disneyi (Aves: Rallidae) and a description of a new species from Oligo-Miocene deposits at Riversleigh, northwestern Queensland, Australia. 17 pp. (in English). Records of the Australian Museum 63: 61-77.