Quantum-Classical Correspondence of Dynamical Observables, Quantization   and the Time of Arrival Correspondence Problem
  We raise the problem of constructing quantum observables that have classical counterparts without quantization. Specifically we seek to define and motivate a solution to the quantum-classical correspondence problem independent from quantization and discuss the general insufficiency of prescriptive quantization, particularly the Weyl quantization. We demonstrate our points by constructing time of arrival operators without quantization and from these recover their classical counterparts. 
Eric A. Galapon (Theoretical Physics Group, National Institute of   Physics, University of the Philippines at Diliman)