A while back my "Advanced Fingering Guide" received a nice review in the ITEA Journal. I have posted it on my blog (with permission):
http://www.dwerden.com/forum/entry.p...phonium-REVIEW
I also made a short YouTube video talking about ONE aspect covered in the book - fingerings for intonation, and it starts with a pop quiz!. (If you want to have your answer ready, the question is: on a 4-valve compensating euphonium, how many fingerings are there for F above the bass clef staff, or G on top of the treble clef staff?)
https://youtu.be/GOqL4SAByyI