Saputra, Irwan, et al. “Identification of Pig Adulterant in Mixture of Fat Samples and Selected Foods Based on FTIR-PCA Wavelength Biomarker Profile”. International Journal on Advanced Science, Engineering and Information Technology, vol. 8, no. 6, Dec. 2018, pp. 2341-8, doi:10.18517/ijaseit.8.6.7689.