According to his own account, it was created during a course at the Computing Center of the University of Madrid in the years 68-69. The original is used by CCOO to screen print it with a run of 500 copies.
However, we have evidence that it belongs to a folder with 6 screen prints of computer-programmed drawings with illustrations of musical scores by R.Barce, Claudio Prieto, Agustín González, Francisco Cano and Carlos Cruz de Castro, of which they edit 50 copies in January 1971. (Museum of Abstract Art of Cuenca, photocopied catalog, vol. II).

1970- A very similar screen print is part of a folder of 6 Screen Prints "Musical", under programming by J.E. Arrechea. Texts by Joaquín Delgado and scores by Ramón Barce, Claudio Prieto, Agustín González, Francisco Estévez, Francisco Cano and Carlos Cruz de Castro. Exhibition at the Honda Hall, Cuenca. Participates in the "Computer Assisted Art exhibition Held" exhibition, National Congress Palace, Madrid. (web Javier Badenes Martín)