Shanshool, Jabir ., and Haider M. T. Al-Qamaje. “Effect of Molecular Weight on Turbulent Drag Reduction With Polyisobutylene”. Al-Nahrain Journal for Engineering Sciences, vol. 11, no. 1, Mar. 2008, pp. 52-59, https://nahje.com/index.php/main/article/view/496.