A. J. Mohammed and Q. H. Kshash, “Comparative study of serum copper concentration in natural copper deficient and healthy Awassi sheep in Al-Najaf city\Iraq”, KUFA J Vet Med Sci, vol. 6, no. 2, pp. 8–16, Dec. 2015, doi: 10.36326/kjvs/2015/v6i24000.