Haydn, J. Quartet No. 21 G major: For 2 violins, viola and violoncello Op.9,No.3. Composed 1769 / Ed. by Wilhelm Altmann (Partitur.). Eulenburg.
Chicago-viite (17. p.)Haydn, Joseph. Quartet No. 21 G Major: For 2 Violins, Viola and Violoncello Op.9,No.3. Composed 1769 / Ed. by Wilhelm Altmann. Partitur. London [u.a.]: Eulenburg.
MLA-viite (8. p.)Haydn, Joseph. Quartet No. 21 G Major: For 2 Violins, Viola and Violoncello Op.9,No.3. Composed 1769 / Ed. by Wilhelm Altmann. Partitur. Eulenburg.
Varoitus: Nämä viitteet eivät aina ole täysin luotettavia.