The inventory list of the Mark Twain Research Foundation
holdings lists this item that may be of interest:

Item #40-93-1-1910  (Letter)  Described as:
Typed letter to John [no last name] signed by Mary Quarles Herdman,
dated August 22, 1950.  In reference to John Quarles and his
family history.  5 1/2 x 7, three pages stapled together.

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