Khuwutthayakorn, Y. , Sopa, K. , Chaiklangmuang , K. , Wongthana, T. , Tangsumpanta, P. and Ekpatanaparnich, S. 2020. Efficacy of light curing unit prototype on surface hardness of resin composite as a function of tilt angle. Chiang Mai Dental Journal. 41, 3 (Dec. 2020), 65–73.