Camargo, Mariana Itimura de, et al. “Mensuration of Sialic Acid Seric Level in Nelore Cattle Exposed and Nonexposed to Bracken Fern (Pteridium Aquilinum)”. Semina: Ciências Agrárias, vol. 29, no. 2, Aug. 2008, pp. 393-8, doi:10.5433/1679-0359.2008v29n2p393.