title: Uncaught Error: Invariant Violation: Element type is invalid: expected a string (for built-in components) or a class/function but got: object
body: <p>I am getting this error:</p>
  <pre><code>Uncaught Error: Invariant Violation: Element type is invalid: expected a string (for built-in components) or a class/function (for composite components) but got: object.
  </code></pre>
  <p>This is my code:</p>
  <pre><code>var React = require('react')
  var ReactDOM =  require('react-dom')
  var Router = require('react-router')
  var Route = Router.Route
  var Link = Router.Link
  
  var App = React.createClass({
    render() {
      return (
        &lt;div&gt;
          &lt;h1&gt;App&lt;/h1&gt;
          &lt;ul&gt;
            &lt;li&gt;&lt;Link to=&quot;/about&quot;&gt;About&lt;/Link&gt;&lt;/li&gt;
          &lt;/ul&gt;
        &lt;/div&gt;
      )
    }
  })
  
  var About = require('./components/Home')
  ReactDOM.render((
    &lt;Router&gt;
      &lt;Route path=&quot;/&quot; component={App}&gt;
        &lt;Route path=&quot;about&quot; component={About} /&gt;
      &lt;/Route&gt;
    &lt;/Router&gt;
  ), document.body)
  </code></pre>
  <p>My <code>Home.jsx</code> file:</p>
  <pre><code>var React = require('react');
  var RaisedButton = require('material-ui/lib/raised-button');
  
  var Home = React.createClass({
    render:function() {
      return (
          &lt;RaisedButton label=&quot;Default&quot; /&gt;
      );
    },
  });
  
  module.exports = Home;
  </code></pre>