http://www.skincarephysicians.com/actinickeratosesnet/index.html
American Academy of Dermatology
Actinic keratoses (AKs) are dry, scaly, rough-textured patches or lesions that form on the outermost layer of the skin after years of exposure to ultraviolet light, such as sunlight. This site links to AKs information resource, including prevention, treatment, increased risk, and more.