Muhamad Norshafiq Ismail, Najihah Rafidi, Raina Jama Awale, and Fathilah Ali, “Preparation and characterization of polylacticacid based polyurethane for environmental friendly packaging materials ”, J. Adv. Res. Fluid Mech. Therm. Sc., vol. 38, no. 1, pp. 16–21, Oct. 2017.