The Pottag Preparatory Melodies
One classic publication I have come back to recently is Preparatory Melodies to Solo Work for French Horn edited by Max P. Pottag. This is a great publication for the moderately advanced student–melodic, short, with some challenges–and I have recently come back to it in my personal practice. It was a book my first major teacher used, Melbern Nixon. Copyrighted in 1941, it is widely available today and inexpensive, Amazon has it here for example.
I remember being puzzled by the line on the cover where it states they are “Selected from the Famous SCHANTL Collection.” Famous Schatl collection?
In my Doctoral research I did actually sort out the source. The etudes are by the Viennese hornist Josef Schantl (1842-1902) and were published in volume III of his four volume Grosse theoritisch-praktisch Horn-Schule (Heilbronn: C. F. Schmidt, 1903). Milan Yancich reprinted volume III as 120 Melodic Pieces Without Accompaniment. He also reprinted volume I as Etudes for the Natural Horn, volume II as Grand Theoretical and Practical Method for the Valve Horn, and vol. IV as Kopprasch, 90 Etudes (this is actually a mixture of Kopprasch and others, as described in this article).
The 98 etudes selected (out of 120) by Pottag from Schantl volume III remain a great, practical collection. For those interested in seeing the original publication I do recommend the Yancich version, but for modern teaching purposes I would recommend the Pottag version as a great, practical publication.