@article{10_4064_aa_5_4_425_426,
     author = {Andrzej Schinzel and Andrzej Wakulicz},
     title = {Sur l'\'equation \ensuremath{\varphi} (x+k)=\ensuremath{\varphi} (x). {II}},
     journal = {Acta Arithmetica},
     pages = {425--426},
     publisher = {mathdoc},
     volume = {5},
     number = {4},
     year = {1959},
     doi = {10.4064/aa-5-4-425-426},
     language = {fr},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/aa-5-4-425-426/}
}