[1]
Colombini, F., Del Santo, D. and Kinoshita, T. 2004. Gevrey-well-posedness for weakly hyperbolic operators with Hölder-continuous coefficients. MATHEMATICA SCANDINAVICA. 94, 2 (Jun. 2004), 267–294. DOI:https://doi.org/10.7146/math.scand.a-14443.