• DOI https://doi.org/10.18177/sym.2017.57.fr.11353
  • PDF https://www.jstor.org/stable/26574470

  • DOI http://dx.doi.org/10.18177/sym.2014.54.sr.10545
  • PDF https://www.jstor.org/stable/26574364

  • PDF https://www.jstor.org/stable/41225239