SSpectral Geometry of Partial Differential Operators (Open AcSpectral Geometry of Partial Differential Operators (Open Access)de Michael Ruzhansky, Makhmud Sadybekov, Durvudkhan SuraganMateriasSpectral geometryPartial differential operatorsGéométrie spectraleOpérateurs différentiels partielsMathematicsMathematical foundationsFunctional analysis & transformsDifferential calculus & equations