• DOI http://dx.doi.org/10.18177/sym.2015.55.sr.10881
  • PDF https://www.jstor.org/stable/26574396

  • DOI http://dx.doi.org/10.18177/sym.2014.54.sr.10628

  • DOI http://dx.doi.org/10.18177/sym.2014.54.fr.10669