Suhartono, S., Prastyo, D. D., Kuswanto, H., & Lee, M. H. (2018). Comparison between VAR, GSTAR, FFNN-VAR and FFNN-GSTAR Models for Forecasting Oil Production. MATEMATIKA, 34(1), 103–111. https://doi.org/10.11113/matematika.v34.n1.1040