1. Aba, M.A., 1995. Studies on the reproductive endocrinology of llamas and alpacas from mating throughout early pregnancy. Masters Thesis. Swedish University of Agricultural Sciences, Uppsala, pp. 11–78.
2. Heterologous radioimmunoassay for llama and alpaca luteinizing hormone with a monoclonal antibody, an equine standard and a human tracer;Aba;Acta Vet. Scand.,1995
3. Endocrine changes after mating in pregnant and non-pregnant llamas and alpacas;Aba;Acta Vet. Scand.,1995
4. Endocrine changes during early pregnancy in the alpaca;Aba;Anim. Reprod. Sci.,1997
5. Hormonal interrelationships in reproduction of female llamas and alpacas;Aba;Acta Univ. Agricult. Sueciae Vet.,1998