@article{701680,
     title = {On singularities of almost periodic functions},
     booktitle = {Proceedings of the 20th Winter School "Geometry and Physics"},
     series = {GDML\_Books},
     publisher = {Circolo Matematico di Palermo},
     address = {Palermo},
     year = {2001},
     pages = {207-211},
     mrnumber = {MR1826693},
     zbl = {1001.42004},
     url = {http://dml.mathdoc.fr/item/701680}
}

Zając, Mariusz. On singularities of almost periodic functions, dans Proceedings of the 20th Winter School "Geometry and Physics", GDML_Books,  (2001), pp. 207-211. http://gdmltest.u-ga.fr/item/701680/