N. A. Harun, N. S. Md Tahier, N. N. Kamaruddin, M. Mamat, and S. Kassim, “Emulsion Polymerization of Poly(Methacrylic Acid) Nanoparticles: Effects of Different Cationic Surfactants”, ajc, vol. 30, no. 10, pp. 2299–2304, Aug. 2018.