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Continue to ChatON THE MEAN, GAUSS, THE SECOND GAUSSIAN AND THE SECOND MEAN CURVATURE OF THE HELICOIDAL SURFACES WITH LIGHT-LIKE AXIS IN R-1(3) - https://avesis.gazi.edu.tr/yayin/dc6e8b49-a864-46c1-b06d-7aba20e2d15e/on-the-mean-gauss-the-second-gaussian-and-the-second-mean-curvature-of-the-helicoidal-surfaces-with-light-like-axis-in-r-13