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Continue to ChatConformally Osserman Lorentzian manifolds satisfying a certain condition on the Ricci tensor - https://avesis.istanbul.edu.tr/publication/details/8b675984-1d42-4fbb-82b9-d640d81fdec1/conformally-osserman-lorentzian-manifolds-satisfying-a-certain-condition-on-the-ricci-tensor