I have always liked the work of J. C. Leyendecker. He was a master draftsman and could do more than most artists with just a few strokes of the brush. Below are some of his finished and studiess.
“Joseph Christian Leyendecker (March 23, 1874 – July 25, 1951) was a pre-eminent American illustrator. He is best known for his poster, book, and advertising illustrations, the iconic trade character known as the Arrow Collar Man, and his many covers for the Saturday Evening Post” http://en.wikipedia.org/wiki/J._C._Leyendecker