Check out Paul Pepera’s free reference pack.
Concept artist Paul Pepera took over 300 photographs at the NASA Johnson Space Center in Houston, and decided to provide these useful pictures free of charge through his Gumroad page. Check it out by clicking on the link below. Enjoy!
Want to help us grow our resources section? If a resource has helped you greatly please e-mail it to me or any suggestions to: firstname.lastname@example.org. I will be keeping this list updated as I discover new entries. Thank you--