@article{BUMI_2011_9_4_1_a0,
     author = {Morandi, Omar and Barletti, Luigi and Frosali, Giovanni},
     title = {Perturbation {Theory} in {Terms} of a {Generalized} {Phase-Space} {Quantization} {Procedure}},
     journal = {Bollettino della Unione matematica italiana},
     pages = {1--18},
     publisher = {mathdoc},
     volume = {Ser. 9, 4},
     number = {1},
     year = {2011},
     zbl = {1234.81078},
     mrnumber = {2797463},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/BUMI_2011_9_4_1_a0/}
}