Non-null Slant Ruled Surfaces
  In this study, we define some new types of non-null ruled surfaces called slant ruled surfaces in the Minkowski 3-space E_1^3. We introduce some characterizations for a non-null ruled surface to be a slant ruled surface in E_1^3. Moreover, we obtain some corollaries which give the relationships between a non-null slant ruled surface and its striction line in E_1^3. 
Mehmet \"Onder
math.DG