Sweet V.I. Design of printed editions [Electronic resource] : / V. I. Sweet – Electronic text data. — Kyiv: Igor Sikorsky Kyiv Polytechnic Institute, 2022. – 66 p. . The fretboard was provided by the Methodical Council of Igor Sikorsky Kyiv Polytechnic Institute. Protocol No. 5 dated 05/25/2022 https://ela.kpi.ua/handle/123456789/47787