Tetralogue: I'm Right, You're Wrong
Timothy Williamson
Timelike Infinity
Stephen Baxter
Xeelee (2)
Vacuum Diagrams
Xeelee (5)
Sketching the basics by Koos Eissen Roselien Steur (z-lib.org)
KODAK Capture software
Drawing on the Right Side of the Brain: The Definitive, 4th ...
Betty Edwards