I recently acquired a new book on classical life drawing that I highly recommend. It is called "Classical Life Drawing Studio" by James McElhinney and the Instructors of the Art Students League of New York. There are dozens of high quality reproductions of classical life drawings by Harvey Dinnerstein, Jack Faragasso, George Bridgeman among others and their students.
Harvey Dinnerstein, Figure Studio, 1978, pastel on board
Hans Peter Hansen, charcoal on paper, Student of George Bridgeman