1. AMERICAN ORNITHOLOGIST'S UNION, 1886 The code of nomenclature and check-list of North American birds. New York: American Ornithologist's Union. Pp 392.
2. Chimney Swifts Nesting in a Barn
3. ASKINS, R. A., LYNCH, J. F. and GREENBERG, R., 1990 Population declines in migratory birds in eastern North America. Current ornithology 7: 1-57.
4. AUDUBON, J. J., 1839 Synopsis of the birds of North America. Edinburgh: Adam & Charles Black. Pp 359.
5. BAIRD, S. F., 1845 Catalogue of birds found in the neighborhood of Carlisle, Cumberland County, Pa. The literary record and journal of the Linnean Association of Pennsylvania College 1: 249-257.