@article{10_4064_aa137_3_6,
     author = {Yasutaka Ihara and V. Kumar Murty and Mahoro Shimura},
     title = {On the logarithmic derivatives of
 {Dirichlet} $L$-functions at $s=1$},
     journal = {Acta Arithmetica},
     pages = {253--276},
     publisher = {mathdoc},
     volume = {137},
     number = {3},
     year = {2009},
     doi = {10.4064/aa137-3-6},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/aa137-3-6/}
}