Edlund, L. (1974). Modus Vetus: Sight Singing and ear-training in major/minor tonality / Lars Edlund. Hansen / Chester Music.
Chicago-viite (17. p.)Edlund, Lars. Modus Vetus: Sight Singing and Ear-training in Major/minor Tonality / Lars Edlund. Stockholm/New York: Hansen / Chester Music, 1974.
MLA-viite (8. p.)Edlund, Lars. Modus Vetus: Sight Singing and Ear-training in Major/minor Tonality / Lars Edlund. Hansen / Chester Music, 1974.
Varoitus: Nämä viitteet eivät aina ole täysin luotettavia.