These images are free to use as you like as long as you attribute to this website ( Since the images have the url in them, using them is okay. If you make modifications it’s okay, as long as you still attribute. The license can be found here.

These images are in the book SpaceWars, but you don’t have to read the book to understand them.

The Backup, if these images take too much time to load, then check out theĀ imgur backups. The ones here are the full size uncompressed versions, so they may take some time to load.