Yassen, Z.N. and Hummudi, I.M. 2021. Influence of Different Wax Hardening Agents on Surface Roughness of Refractory Cast Investment Materials: surface roughness of refractory investment material. Journal of Techniques. 3, 3 (Sep. 2021), 91–95. DOI:https://doi.org/10.51173/jt.v3i3.326.