Abbasi. , K., Khuhawar, M., & Bhanger, M. (2010). Ethyl Chloroformate as Derivatizing Reagent for Gas Chromatographic Determination of Norephedrine, Ephedrine and Pseudoephedrine in Pharmaceutical Preparation. Asian Journal of Chemistry, 21(2), 1145–1154. Retrieved from https://asianpubs.org/index.php/ajchem/article/view/18802