Become a Full Member and get the official Linkage Tour and the official Starting Aid. This information alone will pay for your membership
Yes they were from the same typewriter or stamp used when the data card was filled out. Same Idea as when you would pay for gas with your credit card back in the day. There would be multiple copies made from a single strike. They are called "carbonless copies" Good article on how it works here.https://en.wikipedia.org/wiki/Carbonless_copy_paper