E. Abulyazied, D., N. A. Mansour, A. M. Mazrouaa, and M. G. Mohamed. “Physical Properties of Polyacrylamide/Polyvinylalcohol Silica Nanocomposites”. Journal of Research Updates in Polymer Science, vol. 5, no. 1, Apr. 2016, pp. 10-17, doi:10.6000/1929-5995.2016.05.01.2.