Joseph Leonard & Co.
Martin Gengerke notes "Primarily an auction facility for other catalogers - such catalogs are properly listed under those catalogers. While many catalogs have been issued with a wrong date (i.e. using the old year on a catalog just after January 1st), the record is held by Leonard's 3/14/1876 sale, which lists the year as "1676" on the title page. To further complicate matters, it has 3 sections of lots, each starting with lot #1, and the Durst book lists it as an 1871 sale, with the lot count of only the third (and non-numismatic) section."
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