Official Touch controller button images?

We're integrating the Touch controllers into our game, which already has pad support.  In our UI text, we use images for buttons, e.g. "Press (A) to Interact" or "(RT) Shoot", where (A) is an image of the A button, and (RT) the right trigger.

Do you have any official images for the Touch controller buttons, or guidelines we should use?  I'm particularly interested in how you feel the triggers & grip buttons should be represented.