1. Tregear RT. The permeability of skin to molecules of widely differing properties. In: Rook A, Champion RH, eds. Progress in Biological Sciences in Relation to Dermatology, 2nd ed. London: Cambridge University Press; 1964:275–281.
2. Winkelmann RK. The relationship of structure of the epidermis to percutaneous absorption. Br J Dermatol. 1969;81(Suppl 4): 11–22.
3. Marzulli FN. Barrier to skin penetration. J Invest Dermatol. 1962;39:387–393.
4. Lindsay D. Percutaneous penetration. In: Pillsbury DM, Livingood CS, eds. Proceedings of the 12th International Congress of Dermatology. Amsterdam: Excerpta Medica; 1963:407–415.
5. Maibach HI, Feldmann RJ. Effect of applied concentration on percutaneous absorption in man. J Invest Dermatol 1969;52:382.