Garetto, Claudia Ruzhansky, Michael A note on weakly hyperbolic equations with analytic principal part In this note we show how to include low order terms in the C∞ well-posedness results for weakly hyperbolic equations with analytic time-dependent coefficients. This is achieved by doing a different reduction to a system from the previously used one. We find the Levi conditions such that the C∞ well-posedness continues to hold. Hyperbolic equations;Well-posedness;Mathematical Sciences not elsewhere classified 2015-04-15
    https://repository.lboro.ac.uk/articles/journal_contribution/A_note_on_weakly_hyperbolic_equations_with_analytic_principal_part/9387440