http://www.theregister.co.uk/2005/07/20/crazy_frog_battered/ Finally something about that guy you're going to enjoy, I quote: Or maybe you'll enjoy this more?
Aurthur Hayward explains skin reflectance and scattering in a bit more detail http://arthaywood.blogspot.com/2015/07/studying-color-of-skin-and-its.html?m=1