Qaisar, Aneela, et al. “EFFECT OF LIGNOCAINE ADDITION ON THE PROPERTIES OF IRREVERSIBLE HYDROCOLLOID IMPRESSION MATERIAL”. Journal of Ayub Medical College Abbottabad, vol. 31, no. 3, Aug. 2019, pp. 359-63, https://jamc.ayubmed.edu.pk/index.php/jamc/article/view/6018.