Mr. Sanborn explained in an interview that he created the paper scraps the men had found to share the text with the C.I.A. He had mistakenly included them in the folders he gathered about 10 years ago.

This happened during his treatment for metastatic cancer. “I was not sure how long I would be around and I hastily gathered all of my papers together” for the archives, he said. He was stunned to realize, years later, that the scraps had ended up in the collection.