Books/resources for lapsed horn players?
I have an elderly friend who played horn for many decades but has not played much in the past few years. He would like to get his chops back in shape and play on a daily basis. Do you have any recommended books or resources? Are there some good progressive etude books? Horn isn't my instrument, so I'm totally lost, but I'd like to help him out. He played with a community orchestra for many years--I'd guess his level was low advanced? (He knows it will take him a while to get back into shape and that he'll never get back in the shape he was in when he was younger, as he's in his 80s now.)
Thanks in advance.