@article{selfreplicatingmachinesincontinuousspace,
  title = {Self-Replicating Machines in Continuous Space with Virtual Physics},
  author = {Arnold Smith and Peter Turney and Robert Ewaschuk},
  year = {2003},
  eprint = {cs/0304022},
  archivePrefix = {arXiv},
  url = {https://arxiv.org/abs/cs/0304022v1},
}