Problem:
 f (\x. z (\y. x y)) -> z (\y. y)

Proof:
 Higher-Order Church Rosser Processor:
  f (\x. z (\y. x y)) -> z (\y. y)
  critical peaks: 0
   
   
   Higher-Order Closedness Processor:
     all critical pairs are trivial
    
    Qed