SIFAT MEKANIK KOMPOSIT TERHADAP FRAKSI VOLUME SERAT ECENG GONDOK BERMATRIKS POLYESTER. einstein e-j. [Internet]. 2013 Nov. 1 [cited 2026 Mar. 23];1(2). Available from: https://jurnal.unimed.ac.id/2012/index.php/einsten/article/view/5062