Edward,As these are US publications, there has been legal deposit of two copies to the Library of Congress. If they have not disposed of them, there is a possibility of interlibrary loan (https://www.loc.gov/rr/loan/loan-news.html). The books were distributed as an option to Signature customers, so they are not bookstore items. Maybe someone else subscribed to this list has copies? There quite a lot to scan, the 3 books contain approx. 700-800 pages together.
Kari, it’s possible that you have the only surviving copies of those volumes⬦. Nothing shows up in worldcat.org or bookselling sites.
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