%0 Journal Article %T Comment on: “growth, spectroscopic studies, and third order non-linear optical analysis of an organic dicarboxylic acid based single crystal: urea oxalic acid” [Chin. J. Phys., 56 (2018) 1449–1466] %A Sahebi, Ramezan %J Chinese Journal of Physics %@ 0577-9073 %D 2020