For many years now Sigurd M. Rascher's book Top Tones for Saxophone has
been a go to tool for nearly every aspiring saxophonist of any musical
background. The book has been out for over 70 years and is now in its 3rd
edition. Sigurd is pictured in the book holding two saxophones. One is a
vintage 1859 saxophone and the other is a custom key less saxophone used
to demonstrate overtones.