Hi Bernhard! As I was studying lesson 21 found a minor error. It has in the original 32 measures, the book here has 31. The missing measure is the number 30. it consists of three beats the first is a chord: harmonic 13 indication C, E; duration of two beats up stem, 2nd beat natural E bass one beat duration down stem, last beat chord harmonic A, natural C up stem. Thanks a lot for your attention. So long. Elías
Guitars: "La Valenciana" model 113 (1976), "Tres Pinos" SCG-E112 (2007), "Sergio Mercado" Ramírez replica 2011, Arturo Hernández Hauser replica (2014), Karina Mendoza Fleta replica (2016).