This is the paper by Spencer and Collyer in Usenix &#x27;92. The primary reference should likely be <a href="https:&#x2F;&#x2F;www.usenix.org&#x2F;legacy&#x2F;publications&#x2F;library&#x2F;proceedings&#x2F;sa92&#x2F;spencer.pdf" rel="nofollow">https:&#x2F;&#x2F;www.usenix.org&#x2F;legacy&#x2F;publications&#x2F;library&#x2F;proceedin...</a> .