Existence and Uniqueness Results for Double-Free-Boundary Problems in   Fluid Dynamics
  In two space dimensions, we study a general double-free-boundary problem which models a stream flowing through a gravitaional potentiay. ntial-energy terrain. The existence theorem generalizes (by a different proof) a result of A. Beurling. We study the uniqueness question kn two ways. 
Andrew Acker III
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