Sulistyaningrum, Heny, et al. “Analisis Kemampuan Awal 21st Century Skills Mahasiswa Calon Guru SD”. JURNAL PENDIDIKAN DASAR NUSANTARA, vol. 5, no. 1, July 2019, pp. 142-58, https://doi.org/10.29407/jpdn.v5i1.13068.