Reproduction et développement
http://www.tulane.edu/~bfleury/birds/ornithologylectures.html
http://www.paulnoll.com/Oregon/Birds/courtship-systems.html
http://collections.tepapa.govt.nz/Theme.aspx?irn=1010
http://www.ducks.org/DU_Magazine/DUMagazineMarApr2010/4850/WaterfowlMatingSystems.html
http://www.ucs.mun.ca/~dunbrack/4701mating.html
http://www.paulnoll.com/Oregon/Birds/nest-incubation.html
http://en.wikipedia.org/wiki/Avian_incubation