(1917). The Original Guckert's chords for the ukulele at sight: Without notes or teacher. Union Music.
Chicago-viite (17. p.)The Original Guckert's Chords for the Ukulele at Sight: Without Notes or Teacher. Toledo: Union Music, 1917.
MLA-viite (9. p.)The Original Guckert's Chords for the Ukulele at Sight: Without Notes or Teacher. Union Music, 1917.
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