Dae Ho Jin
      A semi-Riemannian manifold of quasi-constant curvature with half lightlike submanifolds
      International Journal of Mathematical Analysis, Vol. 9, 2015, no. 48, 2363-2376
      http://dx.doi.org/10.12988/ijma.2015.58193

Copyright © 2015 Dae Ho Jin. This article is distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.