@article{JRAM_1990__404_153200,
     author = {J. Bourgain},
     title = {Double recurrence and almost sure convergence.},
     journal = {Journal f\"ur die reine und angewandte Mathematik},
     pages = {140--161},
     year = {1990},
     volume = {404},
     zbl = {0685.28008},
     url = {http://geodesic.mathdoc.fr/item/JRAM_1990__404_153200/}
}