@article{10_4064_aa137_3_7,
     author = {Xiannan Li},
     title = {Variation of the argument of the {Riemann} $\xi $ function
 on vertical lines},
     journal = {Acta Arithmetica},
     pages = {277--284},
     publisher = {mathdoc},
     volume = {137},
     number = {3},
     year = {2009},
     doi = {10.4064/aa137-3-7},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/aa137-3-7/}
}