@article{HeinrichsWeck1981,
  author    = {Heinrichs, Horst and Weck, H.},
  title     = {Efficient finite-element structural analysis by interactive graphic mesh generation},
  series = {CIRP Annals. 30 (1981), H. 1},
  journal   = {CIRP Annals. 30 (1981), H. 1},
  pages     = {279 -- 284},
  year      = {1981},
  language  = {en}
}
@book{HeinrichsWeckGillessen1977,
  author    = {Heinrichs, Horst and Weck, H. and Gillessen, R.},
  title     = {Abschlussbericht zum Zeichnungssystem Freedraft zur rechnerunterstuetzten Zeichnungserstellung},
  address   = {Aachen},
  year      = {1977},
  language  = {de}
}