n.a singer who changes register rapidly (popular is Swiss folk songs)

Yodeller of the year
Yodeller gives a an earful
"I'M A FAMOUS YODELLER"
The yodeller who won a million hearts
DON WALSER ; Texas Yodeller
Country Yodeller Sold Millions of Records
Asbestos to Blame for Yodeller Death
Obituary: Bill Callahan ; Hillbilly Yodeller
Cyril Was Mr Music and Boro's Great Yodeller; Family Pays Tribute to Great-Grandad
Vocal tract configurations in yodelling--prospective comparison of two Swiss yodeller and two non-yodeller subjects