By McPherson, M. J.
By Helen Bee, Denise Boyd
By Chambers, Clare
By R. H. F. Hunter (Royal Veterinary University, Copenhagen, and University of Cambridge)
By Kevin R. Loughlin, John Nimmo
By Sue Gerhardt (Private Practice, Oxford, UK)
By Susan F. Murray
By Gilbert, Scott F.
By Emil Novak, Edmund R. Novak, J.Donald Woodruff, Woodruff
By Gray, Sir Muir, Mostyn, David
By Barnett, C.H.
By Williams, Peter L., etc.
By Nilsson, Lennart, etc., Nilsson, Lennart
By Sarah Kowalski
By Daniel C. Dennett