Editorial: Replace dead link target

spec.html

@@ -2346,7 +2346,7 @@ <h1>
           <emu-note>
             <p>Implementers of ECMAScript may find useful the paper and code written by David M. Gay for binary-to-decimal conversion of floating-point numbers:</p>
             <p>
-              David M. Gay. <a href="http://ampl.com/REFS/abstracts.html#rounding">Correctly Rounded Binary-Decimal and Decimal-Binary Conversions</a>. Numerical Analysis, Manuscript 90-10. AT&amp;T Bell Laboratories (Murray Hill, New Jersey). 30 November 1990.<br>
+              David M. Gay. <a href="https://ampl.com/wp-content/uploads/rounding.pdf">Correctly Rounded Binary-Decimal and Decimal-Binary Conversions</a>. Numerical Analysis, Manuscript 90-10. AT&amp;T Bell Laboratories (Murray Hill, New Jersey). 30 November 1990.<br>
               Associated code is available at any <code>netlib</code> repository mirror in files <a href="http://netlib.sandia.gov/fp/dtoa.c">fp/dtoa.c</a> and <a href="http://netlib.sandia.gov/fp/g_fmt.c">fp/g_fmt.c</a>.
             </p>
           </emu-note>