Behavioural Processes, Vol. 63, No. 3. (31 July 2003), pp. 171-175.
Behavioural Processes, Vol. 64, No. 1. (29 August 2003), pp. 23-29.
J Comp Physiol Psychol, Vol. 90, No. 2. (February 1976), pp. 198-202.
Brain Res Brain Res Protoc, Vol. 8, No. 3. (December 2001), pp. 228-235.
Animal Behaviour, Vol. 15, No. 4. (October 1967), pp. 586-594.
J Comp Physiol Psychol, Vol. 64, No. 2. (October 1967), pp. 356-359.
Animal Behaviour, Vol. 62, No. 6. (December 2001), pp. 1059-1065.
J Exp Anal Behav, Vol. 8, No. 6. (November 1965), pp. 347-403.
Animal Behaviour, Vol. 70, No. 2. (1 August 2005), pp. 427-432.
Behavioural Processes, Vol. 40, No. 1. (April 1997), pp. 1-11.
J Comp Psychol, Vol. 117, No. 1. (March 2003), pp. 111-118.
Behavioural Processes, Vol. 67, No. 3. (30 November 2004), pp. 501-509.
Anim Learn Behav, Vol. 4, No. 2. (May 1976), pp. 167-171.
J Comp Psychol, Vol. 99, No. 1. (March 1985), pp. 56-59.
Animal Behaviour, Vol. 15, No. 4. (October 1967), pp. 574-585.
Cognitive Informatics, 2003. Proceedings. The Second IEEE International Conference on (2003), pp. 41-46.
Animal Behaviour, Vol. 26, No. Part 3. (August 1978), pp. 738-745.