An explicit determination of the non-self-adjoint wave equations that satisfy Huygens' principle on Petrov type III background space-times
This work extends previous results of Carminati and McLenaghan for the selfadjoint scalar wave equation on Petrov type III space-times. Conditions are given for the existence or nonexistence of such wave equations.
scientific article; zbMATH DE number 1011099
scientific article