Purnama, D.I. 2020. A Comparison between Nonparametric Approach: Smoothing Spline and B-Spline to Analyze The Total of Train Passengers in Sumatra Island. EKSAKTA: Journal of Sciences and Data Analysis. 20, 1 (Mar. 2020), 73–80. DOI:https://doi.org/10.20885/EKSAKTA.vol1.iss1.art11.