@article{Spektra_2019, title={FRONT MATTER SPEKTRA VOLUME 4 ISSUE 1, APRIL 2019}, volume={4}, url={https://journal.unj.ac.id/unj/index.php/spektra/article/view/12322}, DOI={10.21009/SPEKTRA.04100}, number={1}, journal={Spektra: Jurnal Fisika dan Aplikasinya}, author={Spektra, Editor}, year={2019}, month={Apr.} }