“…Iqbal et al 56,57 used the CF-LIBS method for the analysis of coal. Similarly, Israr et al 58 investigated the presence of heavy metals in coal samples, using a time-integrated spectrometer with the method introduced by Grifoni et al 20 Haq et al 59 used CF-LIBS for the study of a polymer (Chitosan). Ahmed et al 60 used CF-LIBS for the quality control of alloys, by comparing it with ICP-MS in the study of an ironcopper alloy.…”