Origin of the Boolean Model of Information Retrieval
Looking for &quot;Boolean Retrieval&quot; in google scholar with upper date limit finds two papers that seems related from the sixties.
https://heinonline.org/HOL/LandingPage?handle=hein.journals/juraba8&amp;div=16&amp;id=&amp;page=
https://apps.dtic.mil/sti/pdfs/AD0673362.pdf
There is a reference to Non-Boolean retrieval from 1963, hinting that the term was known before.
Try checking the references in these papers.