Ismiyatin, K., Subiyanto, A., Tangdan, I., Nawawi, R., Lina, R.C., Ernawati, R. and Kurniawan, H.J. 2019. The effects of different 650 nm laser diode irradiation times on the viability and proliferation of human periodontal ligament fibroblast cells. Dental Journal. 52, 3 (Sep. 2019), 142–146. DOI:https://doi.org/10.20473/j.djmkg.v52.i3.p142-146.