@Article{SCI:She2008a,
  author =    "J.F. Shepherd and C.R. Johnson",
  title =     "Hexahedral Mesh Generation Constraints",
  journal =   "Journal of Engineering with Computers",
  volume =    "24",
  number =    "3",
  pages =     "195--213",
  year =      "2008",
  keywords =  "meshing",
  url =       "http://www.sci.utah.edu/publications/shepherd07/EWC_hex_constraints.pdf",
}