Black India ink over light blue Col-erase pencil construction on copier paper January 1994 8 x 10 inch
The ink I had done with technical pen, which was typical for me at the time. Tech. pens like Koh-I-Noor's well-known brand Rapidograph work great, but you got to maintain them so that they don't become ruined with dried shellac in the ink. I actually have a Steadtler set from my engineering days.
Avoiding clean-up of the small parts of tech. pens is one of the reasons I now ink with a round lettering brush.