@article{11074,
  author = {Bj{\o}rn Nielsen and Aslak Tveito},
  title = {An Upscaling Method for One-Phase Flow in Heterogeneous Reservoirs; a Weighted Output Least Squares (WOLS) Approach},
  year = {1998},
  journal = {Computational Geosciences},
  volume = {2},
  pages = {93-123,},
}