Update spec/index.html

Co-authored-by: Ted Thibodeau Jr <[email protected]>

Author: hartig

spec/index.html

@@ -10095,7 +10095,7 @@ <h3>SPARQL Algebra</h3>
             We define:</p>
           <p><a href="#defn_algDiff" class="algFct">Diff</a>(<var>Ω<sub>1</sub></var>, <var>Ω<sub>2</sub></var>, <var>expr</var>, |D|, |G|)
             = { <var>μ</var> in <var>Ω<sub>1</sub></var> | for every <var>μ'</var> in <var>Ω<sub>2</sub></var>,
-            either of the following conditions holds:</p>
+            any of the following conditions holds:</p>
           <ul>
             <li><var>μ</var> and <var>μ'</var> are not <a href="#defn_algCompatibleMapping">compatible</a>,</li>
             <li><var>μ</var> and <var>μ'</var> are <a href="#defn_algCompatibleMapping">compatible</a>