Lambers H, Piessens S, Bloem A, Pronk H, Finkel P (1 tháng 10 năm 2006). “Natural skin surface pH is on average below 5, which is beneficial for its resident flora”. International Journal of Cosmetic Science. 28 (5): 359–70. doi:10.1111/j.1467-2494.2006.00344.x. PMID18489300.
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pubmed.ncbi.nlm.nih.gov
Lambers H, Piessens S, Bloem A, Pronk H, Finkel P (1 tháng 10 năm 2006). “Natural skin surface pH is on average below 5, which is beneficial for its resident flora”. International Journal of Cosmetic Science. 28 (5): 359–70. doi:10.1111/j.1467-2494.2006.00344.x. PMID18489300.