@article{BSMF_2010__138_2_231_0,
     author = {Acquistapace, Francesca and Broglia, Fabrizio and Fernando, Jos\'e F. and Ruiz, Jes\'us M.},
     title = {On the finiteness of {Pythagoras} numbers of real meromorphic functions},
     journal = {Bulletin de la Soci\'et\'e Math\'ematique de France},
     pages = {231--247},
     publisher = {Soci\'et\'e math\'ematique de France},
     volume = {138},
     number = {2},
     year = {2010},
     doi = {10.24033/bsmf.2589},
     mrnumber = {2679039},
     zbl = {1197.14060},
     language = {en},
     url = {http://www.numdam.org/articles/10.24033/bsmf.2589/}
}