1. Acosta, M., Mugica, L., Mancina, C., and Ruiz, X., 1996, Resource partitioning between Glossy and White Ibises in a rice field system in southcentral Cuba, Colon. Waterbirds 19: 65–72.
2. Adam, M. D., and des Lauriers, J. R., 1998, Observations of hummingbirds ingesting mineral-rich compounds, J. Field Ornithol. 69: 257–261.
3. Aldrich, E. C., 1939, Notes on the salt-feeding habits of the Red Crossbill, Condor 41: 172–173.
4. Allen, D. L., 1962, Our Wildlife Legacy, 2nd ed., Funk and Wagnalls, New York. Alonso, J. C., 1985, Grit in the gizzard of Spanish Sparrows (Passer hispaniolensis), Vogelwarte 33: 135–143.
5. Anderson, A., 1989, Prodigious Birds: Moas and Moa Hunting in Prehistoric New Zealand, Cambridge University Press, Cambridge, England.