Spektra, Editor. “BACK MATTER SPEKTRA VOLUME 4 ISSUE 1, APRIL 2019”. Spektra: Jurnal Fisika dan Aplikasinya 4, no. 1 (April 30, 2019). Accessed June 21, 2024. https://journal.unj.ac.id/unj/index.php/spektra/article/view/14851.