This assortment is from a range of books from different years, but are pretty good examples of when I would try to focus on classical art through line drawing. The first page was done in 2002 at the Art Institute of Chicago. The top figures are from Cezanne's The Bathers, Hopper's Nighthawks is cropped on the left side (I believe it was temporarily at the Art Institute at the time), and the bottom right quarter is a portrait of Vincent Van Gogh:
Speaking of Van Gogh, I drew a sliced mango in the way I imagined he would in the top right of this page (circa1998). The left side is a line-by-line recration of a drawing by Picasso (whose title and internet link escape me) that I did in 1999. The woman's profile in the bottom right was taken from an art school flyer I had handy at the time (2000).
Rounding out this post are two more artist's portraits. On the is a portrait of the young artist prodigy Amedeo Modigliani (2000). On the right is a quickly-drafted Wasily Kandinsky below a recreation of his signature, both done by brush pen in 2000. I take Kandinsky's philosophies on painting to heart each time I try to work on something abstract.