Ardiansyah, R. and Isna Wijayani 2022. Marketing Strategy to Improve Export Services of PT. Varuna Tirta Prakasya (Persero) in National Market Competition. Jurnal Mantik. 6, 3 (Sep. 2022), 2683-2692. DOI:https://doi.org/10.35335/mantik.v6i3.2924.