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@article{MS2_1955__3_165574, author = {VIDAR THOM\'EE}, title = {Estimates of the {Friedrichs} {-Lewy} type for a hyperbolic equation with three characteristics}, journal = {Mathematica Scandinavica}, pages = {115--123}, publisher = {mathdoc}, volume = {3}, year = {1955}, zbl = {0064.34405}, url = {http://geodesic.mathdoc.fr/item/MS2_1955__3_165574/} }
VIDAR THOMÉE. Estimates of the Friedrichs -Lewy type for a hyperbolic equation with three characteristics. Mathematica Scandinavica, Tome 3 (1955), pp. 115-123. http://geodesic.mathdoc.fr/item/MS2_1955__3_165574/