Manuharawati, R. Sulaiman, H. T. Sutanto, M. Jakfar, and T. Phibeta, “Development of Online Student Olympiad Training Materials for Elementary School Teachers in Magersari Mojokerto Subdistrict in the COVID-19 Pandemic Era”, gandrung, vol. 2, no. 1, pp. 62-72, Feb. 2021.