Al Haromainy, Muhammad Muharrom, et al. “PREDICTION OF MULTIVARIATE TIME SERIES DATA USING ECHO STATE NETWORK AND HARMONY SEARCH”. JUTI: Jurnal Ilmiah Teknologi Informasi, vol. 19, no. 2, July 2021, pp. 111-9, https://doi.org/10.12962/j24068535.v19i2.a1051.