@article{DBLP:journals/cogsci/diSessaGE04,
  author    = {Andrea A. diSessa and
               Nicole M. Gillespie and
               Jennifer B. Esterly},
  title     = {Coherence versus fragmentation in the development of the
               concept of force},
  journal   = {Cognitive Science},
  volume    = {28},
  number    = {6},
  year      = {2004},
  pages     = {843-900},
  ee        = {http://dx.doi.org/10.1016/j.cogsci.2004.05.003},
  bibsource = {DBLP, http://dblp.uni-trier.de}
}