1. D. M. Broom. Professor of Animal Welfare, University of Cambridge. A Usable Definition of Animal Welfare. 1991.

2. M.A. Atock - Federacion Equestre Internationale, and R.R. Williams - The Jockey Club, London. Welfare of competition Horses.

3. M.A. Atock - Federacion Equestre Internationale, and R.R. Williams - The Jockey Club, London. Welfare of competition Horses.

4. Bob Dylan. The times they are a-changin'.