Marilyn J. Brackney
Imagination Factory: Paint a Wet Into Wet Watercolor
"Wet-into-wet" painting is an interesting painting technique described in this website. Included are example images and "Tips and Tricks" for creating your masterpiece.
Olga, Helen, Yuri and Sergey Mataev
Olga's Gallery: Raphael
In-depth biography of Raphael from Olga's Gallery including his style and links to his works one being "Portrait of Pope Leo X with Cardinals Giulio de Medici and Luigi de Rossi."