This primary source comes from the Records of the Patent and Trademark Office, 1836 - 1978.
National Archives Identifier:
7451916Full Citation: Patent Drawing for W. L. Judson's Clasp Locker or Unlocker for Shoes; 8/19/1893; Records of the Patent and Trademark Office, 1836 - 1978, Record Group 241. [Online Version, https://www.docsteach.org/documents/document/patent-drawing-for-w-l-judsons-clasp-locker-or-unlocker-for-shoes, May 6, 2024]