Update README.md

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README.md

@@ -13,7 +13,7 @@ This library is an embedded logic reasoning core. It supports recursive substitu
 2. Consider math algebraic expression problems, such as simplifying 2x+3y-2x+2z, check out unit test code to compute the result and intermediate steps to reach that result: [AlgebraTest.cs](https://github.com/buptkang/CSharp.Logic/tree/master/Test/1.Logic.Algebra).
 
 3. Consider math algebra equation problems, such as simplifying 3y+2x-x+3y=y, check out unit test code to compute the result and intermediate steps to reach that result:
-[*.Equation.*.Test.cs](https://github.com/buptkang/CSharp.Logic/tree/master/Test/2.Logic.Equation)
+[\*.Equation.\*.Test.cs](https://github.com/buptkang/CSharp.Logic/tree/master/Test/2.Logic.Equation)
 
 ## License