1. Fitzpatrick, J. W., Lammertink, M., Luneau, M. D., Gallagher, T. W. & Harrison, B. R. et al. Ivory-billed Woodpecker (Campephilus principalis) persists in Continental North America. Science 308, 1460–1462 (2005).
2. Hill, G. E., Mennill, D. J., Rolek, B. W., Hicks, T. L. & Swiston, K. A. Evidence suggesting that Ivory-billed Woodpeckers (Campephilus principalis) exist in Florida. Avian Conserv. Ecol. 1, 3 (2006).
3. Collins, M. D. Video evidence and other information relevant to the conservation of the Ivory-billed Woodpecker (Campephilus principalis). Heliyon 3, e00230 (2017).
4. Simmons, G. F. Differential Equations with Applications and Historical Notes, McGraw-Hill, New York, USA, pp. 93–100 (1972).
5. Pennycuick, C. J. Predicting wingbeat frequency and wavelength of birds. J. Exp. Biol. 150, 171–185 (1990).