@article{702131,
     title = {Plane waves, biregular functions and hypercomplex Fourier analysis},
     booktitle = {Proceedings of the Winter School "Geometry and Physics"},
     series = {GDML\_Books},
     publisher = {Circolo Matematico di Palermo},
     address = {Palermo},
     year = {1985},
     pages = {[205]-219},
     mrnumber = {MR0853142},
     zbl = {0597.30059},
     url = {http://dml.mathdoc.fr/item/702131}
}

Sommen, F. Plane waves, biregular functions and hypercomplex Fourier analysis, dans Proceedings of the Winter School "Geometry and Physics", GDML_Books,  (1985), pp. [205]-219. http://gdmltest.u-ga.fr/item/702131/