@article{IM_1972__16_142142,
     author = {P.X. Gallagher},
     title = {Primes in {Progressions} to {Prime-Power} {Modulus.}},
     journal = {Inventiones mathematicae},
     pages = {191--201},
     publisher = {mathdoc},
     volume = {16},
     year = {1972},
     zbl = {0246.10030},
     url = {http://geodesic.mathdoc.fr/item/IM_1972__16_142142/}
}