Santos, R.R. dos et al. 2006. Toxicity test and cryopreservation of sheep isolated preantral follicles using glycerol, ethylen glycol, dimethil sulfoxyde and propanediol. Brazilian Journal of Veterinary Research and Animal Science. 43, 2 (Apr. 2006), 250–255. DOI:https://doi.org/10.11606/issn.1678-4456.bjvras.2006.26506.