@article{CMUC_1987__28_4_a2,
     author = {Balcar, Bohuslav and Kal\'a\v{s}ek, Pavel and Williams, Scott W.},
     title = {On the multiple {Birkhoff} recurrence theorem in dynamics},
     journal = {Commentationes Mathematicae Universitatis Carolinae},
     pages = {607--612},
     publisher = {mathdoc},
     volume = {28},
     number = {4},
     year = {1987},
     mrnumber = {928675},
     zbl = {0642.54037},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/CMUC_1987__28_4_a2/}
}