Who Knows by Jimi Hendrix 
    
    ----------------------------------------------------------------------------------g
    --------2------------------------2------------------------------------------------d
    ----------4-4-2-4-2----------------4-4-2-4-2--------------------------------------a
    -1--0---------------4-3-2---1-0---------------4-3-2-1-0---------------------------e
    
     that is the main riff Cox uses but sometimes he varies it like so:
    
    -----2-------------2---------------------2------------------------d
    -------4-4-2---------4-4-2-4-2------------------------------------a
    -1-0---------4-3-2-------------4-3-2-1-0--------------------------e