1. R.W. Duffin. 2008. How Equal Temperament Ruined Harmony (and Why You Should Care). W. W. Norton. https://books.google.co.uk/books?id=i5LC7Csnw7UC R.W. Duffin. 2008. How Equal Temperament Ruined Harmony (and Why You Should Care). W. W. Norton. https://books.google.co.uk/books?id=i5LC7Csnw7UC
2. Alexander John Ellis. 1885. On the musical scales of various nations. From The journal of the society of arts 33 1688 (1885) 485--527 p. Alexander John Ellis. 1885. On the musical scales of various nations. From The journal of the society of arts 33 1688 (1885) 485--527 p.
3. Haye Hinrichsen. 2016. Revising the musical equal temperament. Revista Brasileira de Ensino de FÃsica 38 (00 2016). http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1806-11172016000100410&nrm=iso Haye Hinrichsen. 2016. Revising the musical equal temperament. Revista Brasileira de Ensino de FÃsica 38 (00 2016). http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1806-11172016000100410&nrm=iso