On spectral multiplicities {2, 4,..., 2^n} for totally ergodic   Z^2-actions
  For totally ergodic Z^2-actions a collection of weak limits provide the set {2,4, ..., 2 ^ n} of spectral multiplicities for their tensor product. Our conditions allow to obtain a similar result for mixing actions via some limit procedure. 
R. A. Konev and V. V. Ryzhikov
math.DS