@article{holland20061,
  title     = {Studying Complex Adaptive Systems},
  author    = {Holland, John H.},
  year      = {2006},
  journal   = {Journal of Systems Science and Complexity},
  volume    = {19},
  number    = {1},
  pages     = {1-8},
  doi       = {10.1007/s11424-006-0001-z},
}