1. Franke AA, Li X, Lai JF: Pilot study of the pharmacokinetics of betel nut and betel quid biomarkers in saliva, urine, and hair of betel consumers. Drug Test Anal. 2016 Oct;8(10):1095-1099. doi: 10.1002/dta.1912. Epub 2015 Dec 1. [PubMed:26619803 ]
  2. Hu CW, Chang YZ, Wang HW, Chao MR: High-throughput simultaneous analysis of five urinary metabolites of areca nut and tobacco alkaloids by isotope-dilution liquid chromatography-tandem mass spectrometry with on-line solid-phase extraction. Cancer Epidemiol Biomarkers Prev. 2010 Oct;19(10):2570-81. doi: 10.1158/1055-9965.EPI-10-0483. Epub 2010 Aug 16. [PubMed:20713654 ]