Where are the L1 L2 R1 R3 buttons?

L1 is the top button on the face with the cable on you press with your left index finger. R1 is the top button on the face with the cable on you press with your right index finger. L2 is the button below L1. R3 is when you press down the right analog stick to make a clicking sound. See link below for a clearer view.