.
I suggest that you download the indexes to
First Days, the journal of the American FDC Society, and search for articles about the cachetmakers of interest to you.
http://www.afdcs.org/firstdays.htmlThen, evaluate whether/not to buy the complete digital archive of the journal, with every issue from 1955 thru 2017.
http://www.afdcs.org/FDarchive.htmlCheers,
/s ikeyPikey (who suggests that you not ask Don what he thinks of the journal paywall)
