Putra, V. G. V., Mohamad, J. N. and Yusuf, Y. (2021) “A New Model to Calculate Stress Relaxation of Viscoelastic Material for Polyester-Wool-Spandex Yarn with Analytical Mechanics Approach”, Jurnal Penelitian Fisika dan Aplikasinya (JPFA), 11(2), pp. 94–105. doi: 10.26740/jpfa.v11n2.p94-105.