APA

Editorial Director Gallagher B., Brewer J. (. D., . (2009). Why do birds have beaks?. China: Miles Kelly.

Chicago

Editorial Director Gallagher Belinda, Brewer Jo (ART Director), . 2009. Why do birds have beaks?. China: Miles Kelly.

Harvard

Editorial Director Gallagher B., Brewer J. (. D., . (2009). Why do birds have beaks?. China: Miles Kelly.

MLA

Editorial Director Gallagher Belinda, Brewer Jo (ART Director), . Why do birds have beaks?. China: Miles Kelly. 2009.