Clifton, P. G. "Gonadal steroids and memory formation." Neural and Behavioural Plasticity: The Use of the Domestic Chick as a Model. : Oxford University Press, 1991-06-06. Oxford Scholarship Online. 2012-03-22. Date Accessed 19 May. 2013 <http://www.oxfordscholarship.com/view/10.1093/acprof:oso/9780198521846.001.0001/acprof-9780198521846-chapter-19>.
Clifton, P.(1991-06-06). Gonadal steroids and memory formation. In Neural and Behavioural Plasticity: The Use of the Domestic Chick as a Model. : Oxford University Press. Retrieved 19 May. 2013, from http://www.oxfordscholarship.com/view/10.1093/acprof:oso/9780198521846.001.0001/acprof-9780198521846-chapter-19.
Clifton, P. G. "Gonadal steroids and memory formation." In Neural and Behavioural Plasticity: The Use of the Domestic Chick as a Model. : Oxford University Press, 1991-06-06. http://www.oxfordscholarship.com/view/10.1093/acprof:oso/9780198521846.001.0001/acprof-9780198521846-chapter-19.
Clifton PG. Gonadal steroids and memory formation. In: Andrew RJ. Neural and Behavioural Plasticity: The Use of the Domestic Chick as a Model. Oxford University Press; 1991. http://www.oxfordscholarship.com/view/10.1093/acprof:oso/9780198521846.001.0001/acprof-9780198521846-chapter-19. Accessed May 19, 2013.