Aspects of Guitar music of the Twentieth Century
by A. Gilardino
History of the Literature of the Lute ad Guitar – II. The Sixteenth Century
by R. Chiesa
Notes on researches into the ethnic origins of the Guitar and the Lute
by E.F. Ciurlo
• Invariant morphology
• Principle of progressive complication, leading the original instruments to increasingly complex forms
• Research method
• Conclusions