Vishlitzky, Natan. "Storage and Retrieval System for a Plurality of Data Storage Mediums." U.S. Patent number 5724321. Washington DC: United States Patent and Trademark Office, 1998.

Vishlitzky, Natan. "Storage and Retrieval System for a Plurality of Data Storage Mediums." U.S. Patent number 5724321. Washington DC: United States Patent and Trademark Office, 1998.