1. A system to maximize the maintenance of genetic variability in small populations;Alderson,1992
2. APSL, 2010. Studbook Regulation. Associação Portuguesa de Criadores do Cavalo Puro-sangue Lusitano. Cascais, Portugal.
3. Azor, P.J., 2009. Horse Biodiversity and their Contribution to Rural Development in Spain. EAAP. 60th Annual Meeting, Barcelona, Spain.
4. The value of using probabilities of gene origin to measure genetic variability in a population;Boichard;Genet. Sel. Evol.,1997
5. Genetic aspects of domestication, breeds and their origins;Bowling,2000