title: The type 'Expression<>' is defined in an assembly that is not referenced
body: <p>In ASP.NET MVC 4.5.2 Framework, after typing <code>@Html.LabelFor()</code> or <code>@Html.EditorFor()</code> in a view, I'm getting this error:</p>
  <blockquote>
  <p>The type '<code>Expression&lt;&gt;</code>' is defined in an assembly that is not referenced. You must add a reference to assembly '<code>System.Core, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</code>'.</p>
  </blockquote>
  <p>I have added assembly reference System.Core.dll, Version 4.0.0.0, Runtime Version v4.0.30319, and also I did in web.config.</p>