Zheng, Sai-Jing, Jun Yang, Bai-Zhan Liu, Wen-Jing Zhu, Li Yao, Wen-Bo Gu, and Rong Qian. 2011. “Rapid Determination of Four Tobacco-Specific Nitrosamines in Mainstream Cigarette Smoke by UPLC-TOF-MS”. Asian Journal of Chemistry 24 (3):1147-50. https://asianpubs.org/index.php/ajchem/article/view/8728.