More skull anatomy drawings to understand the human head and face. A real influence is Ryan Kingslien and many other Z Brush artists that show how to sculpt a face and head from a position of knowledge (how particular skull bones influence the surface of the face, correct proportions using features of the skull that influence each other and the correct design of the skull, subtle differences male/female, and other good advice position of eye in orbit and the position of the lips to the teeth and so on) Great stuff - its now making me consider anatomy and sculpting in a completely different way - now looking at my feeble attempt in ZBrush - must do better, much better.
Other references used, Scott Eaton, Wiki - understand each part of the skull and Gray's Antomy (the book not the tv series)