@article{10_4007_annals_2004_160_839,
     author = {Jeffrey S. Geronimo and Hugo J. Woerdeman},
     title = {Positive extensions, {Fej\'er-Riesz} factorization and autoregressive filters in two variables},
     journal = {Annals of mathematics},
     pages = {839--906},
     publisher = {mathdoc},
     volume = {160},
     number = {3},
     year = {2004},
     doi = {10.4007/annals.2004.160.839},
     mrnumber = {2144970},
     zbl = {1084.42019},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4007/annals.2004.160.839/}
}