A modern-day camera lucida, and David Hockney's controversial theory about old masters
How to Draw 3D Letter N - drawing sheet
Intermediate: Icon Tutorial – BMCC Makerspace
Drawing 3D Art
LuisTolentino-Blog
Cheat Code for Drawing: The NeoLucida Lets You Trace 3D Objects onto Paper - Core77
LuisTolentino-Blog
AWESOME Image Tracing Tool - FREE PDF Plan +STL Files for 3D
Core77 / Nick LiCausi
Learning to Draw - MS POLLOCK'S WEEBLY