N. Verma, V. Awinashe, and U. Palekar, “To Evaluate the Variation in Shade by A Spectrophotometer of Porcelain Fused to Metal Samples With Respect to Repeated Firing and Variation In Lot of Ceramic - An In-vitro Study”, JPFA, vol. 27, no. 2, pp. 53–59, Nov. 2018.