A new in vitro approach for determining the water resistance of sunscreen products, validated by a blinded ring test. - Pissavini, M.; Pouradier, F.; Wiener, G.; Contier, M.; Kolbe, L.; Nogueira, L.; Lapalud, P.; Renner, G.; Matts, P. J. (International Journal of Cosmetic Science, 2025)