Finlan, L. E.; Kernohan, N. M.; Thomson, G.; Beattie, P. E.; Hupp, T. R.; Ibbotson, S. H. (2005). "Differential effects of 5-aminolaevulinic acid photodynamic therapy and psoralen + ultraviolet a therapy on p53 phosphorylation in normal human skin in vivo". British Journal of Dermatology. 153 (5): 1001–10. doi:10.1111/j.1365-2133.2005.06922.x. PMID16225614.
Finlan, L. E.; Kernohan, N. M.; Thomson, G.; Beattie, P. E.; Hupp, T. R.; Ibbotson, S. H. (2005). "Differential effects of 5-aminolaevulinic acid photodynamic therapy and psoralen + ultraviolet a therapy on p53 phosphorylation in normal human skin in vivo". British Journal of Dermatology. 153 (5): 1001–10. doi:10.1111/j.1365-2133.2005.06922.x. PMID16225614.