sounds playing paralell like background,walking, gunshot. I want to stop a specific sound. how can i do it

i am using audio source for for each paralell playing sound for example for player walk, background music and for gunshot, i am using audio source now i want to to stop the sound when player stop walking how to do it…

Thanks i will really appreciate if any anyone give me the answer.

http://docs.unity3d.com/Documentation/ScriptReference/AudioSource.Stop.html