The International Pau Casals Cello Competition is held in Germany once every four years . The International Pablo Casals Cello Competition is held in Kronberg and Frankfurt am Main , Germany , under the auspices of the Kronberg Academy once every four years , starting in 2000 , in order to discover and further the careers of the future cello elite , and is supported by the Pau Casals Foundation , under the patronage of Marta Casals Istomin .