Y. Zhu, B. J. Pandya and H. K. Choi, “Prevalence of Gout and Hyperuricemia in the US General Population, the National Health and Nutrition Examination Survey 2007-2008,” Arthritis & Rheumatism, Vol. 63, No. 10, 2011, pp. 3136-3141. http://dx.doi.org/10.1002/art.30520
 R. C. Lawrence, D. T. Felson, C. G. Helmick, L. M. Arnold, H. Choi, R. A. Deyo, et al. (For the National Arthritis Data Workgroup), “Estimates of the Prevalence of Arthritis and Other Rheumatic Conditions in the United States, Part II,” Arthritis & Rheumatism, Vol. 58, No. 1, 2008, pp. 26-35.
 J. D. Bieber, R. S. Terkeltaub, “Gout: On the Brink of Novel Therapeutic Options for an Ancient Disease,” Arthritis & Rheumatism, Vol. 50, No. 8, 2004, pp. 24002414.
 H. R. Schumacher Jr. and L. X. Chen, “The Practical Management of Gout,” Cleveland Clinic Journal of Medicine, Vol. 75, Suppl. 5, 2008, pp. S22-S25.
 H. K. Choi, K. Atkinson, E. W. Karlson, W. Willett and G. Curhan, “Purine-Rich Foods, Dairy and Protein Intake, and the Risk of Gout in Men,” New England Journal of Medicine Vol. 350, No. 11, 2004, pp. 1093-1103.
 L. A. Rogers, K. E. Crews, S. G. Long, K. M. Patterson and J. E. McCune, “Evaluation of Chromatographic Methods for Drug Products Containing Polar and Non-Polar Molecules Using Reversed Phase, Hydrophilic Interaction, and Ion Exchange Chromatography,” Journal of Liquid Chromatography & Related Technologies, Vol. 32, No. 15, 2009, pp. 2246-2264.
 N. Yamaoka, K. Kaneko, Y. Kudo, M. Aoki, M. Yasuda, K. Mawatari, et al., “Analysis of Purine in Purine-Rich Cauliflower,” Nucleosides, Nucleotides and Nucleic Acids, Vol. 29, No. 4-5, 2010, pp. 518-521.
 L. F. Cavalieri, A. Bendich, J. F. Tinker and G. B. Brown, “Ultraviolet Absorption Spectra of Purines, Pyrimidines and Triazolopyrimidines,” Journal of the American Chemical Society, Vol. 70, No. 11, 1948, pp. 3875-3880.