Play sound on click GUIbutton

So far, for a school project, I have been able to get a GUI button to display upon detection of an imagetarget. What I haven't been able to figure out however is how to get sound to play when this button is clicked even though I get no error. The code for the popup GUI button can be found below.

I think the error is somewhere under the line "// do something on button click".

`

 using UnityEngine;
 using System.Collections;
 using Vuforia;
 
 public class ButtonPopup : MonoBehaviour, ITrackableEventHandler
 {
     public AudioClip Gymnopedie;
     public Texture btntexture;
     public Texture LogoTexture;
     public Texture MobiliyaTexture;
 
     private TrackableBehaviour mTrackableBehaviour;
 
     private bool mShowGUIButton = false;
     private Rect mButtonRect = new Rect(50, 50, 120, 60);
 
     void Start()
     {
         mTrackableBehaviour = GetComponent<TrackableBehaviour>();
         if (mTrackableBehaviour)
         {
             mTrackableBehaviour.RegisterTrackableEventHandler(this);
         }
     }
 
     public void OnTrackableStateChanged(
                                     TrackableBehaviour.Status previousStatus,
                                     TrackableBehaviour.Status newStatus)
     {
         if (newStatus == TrackableBehaviour.Status.DETECTED ||
             newStatus == TrackableBehaviour.Status.TRACKED)
         {
             mShowGUIButton = true;
         }
         else
         {
             mShowGUIButton = false;
         }
     }
 
     void OnGUI()
     {
         if (mShowGUIButton)
         {
             // draw the GUI button
             if (GUI.Button(mButtonRect, "Turtle"))
            
             {
                 // do something on button click
                 this.gameObject.AddComponent<AudioSource>();
                 this.GetComponent<AudioSource>().clip = Gymnopedie;
                 this.GetComponent<AudioSource>().Play();
 
 
 
 
             }
         }
     }
 }

Help would be greatly appreciated! :)