\ProvidesPackage{serbianpart} \renewcommand*{\thepart}{\ifcase\value{part}\or Prvi\or Drugi\or Tre\'{c}i\or \v{C}evrti\or Peti\or \v{S}esti\or Sedmi\or Osmi\or Deveti\or Deseti\or Jedanaesti\or Dvanaesti\or Trinaesti\or \v{C}etrnaesti\or Petnaesti\or \v{S}esnaesti\or Sedamnaesti\or Osamnaesti\or Devetnaesti\or Dvadeseti \fi\space}