W. Nessa, Y. Hartono, and C. Hiltrimartin, “Pengembangan Buku Siswa Materi Jarak pada Ruang Dimensi Tiga Berbasis Science, Technology, Engineering, and Mathematics (STEM) Problem-Based Learning di Kelas X”, J. Elemen, vol. 3, no. 1, pp. 1–14, Jan. 2017.