Wilkinson, William "Bill" Albert (2003) [1996, 1984]. "The H89 Worm: Memory Testing the H89". Bill Wilkinson's Heath Company Page. Archived from the original on 2021-12-13. Retrieved 2021-12-13.
Wilkinson, William "Bill" Albert (2003) [1996, 1984]. "The H89 Worm: Memory Testing the H89". Bill Wilkinson's Heath Company Page. Archived from the original on 2021-12-13. Retrieved 2021-12-13.