... 20. Findlay, G. H., J. G. L. Morrison, and I. W. Simson, ``Exogenous Ochronosis and Pigmented
Colloid Milium From Hydroquinone Bleaching Creams,'' British Journal of Dermatology, 93:613-622, 1975. 21. ...
http://www.fda.gov/OHRMS/DOCKETS/98fr/E6-14263.htm