18. Gies P, Roy C, McLennan A, et al. Ultraviolet protection factors for clothing: an intercomparison of measurement systems. Photochem Photobiol. 2003;77(1):58-67.

18. Gies P, Roy C, McLennan A, et al. Ultraviolet protection factors for clothing: an intercomparison of measurement systems. Photochem Photobiol. 2003;77(1):58-67.