Zheng, X.F., and Q. Lian. “Preparation and Characterization of Magnetic Co0.5Mn0.5Fe2O4-Chitosan Nanoparticles As Surfactants in Oilfield”. Asian Journal of Chemistry, vol. 26, no. 14, July 2014, pp. 4499-03, doi:10.14233/ajchem.2014.17466.