Fix typo in docs

Author: exogen

README.md

@@ -272,9 +272,9 @@ One&nbsp;of… <br>
 <td valign="top" valign="top" rowspan="1">
 
 Indicator to render when scrolling is allowed in the requested direction. If
-given a function, it will be passed the overflow state and and object containing
-the `viewport` ref (you can use the `refs` parameter to render an indicator that
-is also a button that scrolls the viewport).
+given a function, it will be passed the overflow state and an object containing
+the `viewport` ref. You can use this `refs` parameter to render an indicator
+that is also a button that scrolls the viewport (for example).
 
 </td>
 </tr>

src/index.js

@@ -367,9 +367,9 @@ OverflowIndicator.displayName = 'Overflow.Indicator';
 OverflowIndicator.propTypes = {
   /**
    * Indicator to render when scrolling is allowed in the requested direction.
-   * If given a function, it will be passed the overflow state and and object
-   * containing the `viewport` ref (you can use the `refs` parameter to render
-   * an indicator that is also a button that scrolls the viewport).
+   * If given a function, it will be passed the overflow state and an object
+   * containing the `viewport` ref. You can use this `refs` parameter to render
+   * an indicator that is also a button that scrolls the viewport (for example).
    */
   children: PropTypes.oneOfType([PropTypes.node, PropTypes.func]),
   /**