@article{AUPO_2011_50_1_a4,
     author = {El Farissi, Abdallah and Bela{\"\i}di, Benharrat},
     title = {Complex {Oscillation} {Theory} of {Differential} {Polynomials}},
     journal = {Acta Universitatis Palackianae Olomucensis. Facultas Rerum Naturalium. Mathematica},
     pages = {43--52},
     year = {2011},
     volume = {50},
     number = {1},
     mrnumber = {2920698},
     zbl = {1244.34108},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/AUPO_2011_50_1_a4/}
}