Loka Andari, I. A. K. M., Darsana, I. W. and Sri Asri, A. (2019) “Pengaruh Model Problem Based Learning (PBL) Berbasis Portofolio Terhadap Hasil Belajar IPS”, International Journal of Elementary Education, 3(4), pp. 373–380. doi: 10.23887/ijee.v3i4.21309.