Polygonal chains cannot lock in 4D

Roxana Cocan, Joseph O Rourke. Polygonal chains cannot lock in 4D. Comput. Geom., 20(3):105-129, 2001.

@article{CocanO01,
  title = {Polygonal chains cannot lock in 4D},
  author = {Roxana Cocan and Joseph O Rourke},
  year = {2001},
  researchr = {https://researchr.org/publication/CocanO01},
  cites = {0},
  citedby = {0},
  journal = {Comput. Geom.},
  volume = {20},
  number = {3},
  pages = {105-129},
}