at the top right hand side of the screen. Try it now so that you can become
familiar with the contents.
When you are using the reference window if you click outside the window it will disappear from your screen. To return the window click on "reference"on the view bar at the bottom (or top ) of your screen.
If you click on the icon and nothing happens it is probably because you already have a reference window open which is hidden. Click on "reference " on the view bar to return the window to your screen.