Dewi, N. L. S., G. Suweken, and I. G. P. Sudiarta. “Development of Mathematics Learning Tools through Scientific Approach With Problem Based Learning (PBL) Settings to Improve Motivation and Learning Achievement”. Jurnal Pendidikan Dan Pengajaran, vol. 52, no. 1, Apr. 2019, pp. 33-39, doi:10.23887/jpp.v52i1.17247.