@article{JTNB_1997__9_1_51_0,
     author = {Lemmermeyer, Franz},
     title = {Unramified quaternion extensions of quadratic number fields},
     journal = {Journal de th\'eorie des nombres de Bordeaux},
     pages = {51--68},
     publisher = {Universit\'e Bordeaux I},
     volume = {9},
     number = {1},
     year = {1997},
     mrnumber = {1469661},
     zbl = {0890.11031},
     language = {en},
     url = {http://www.numdam.org/item/JTNB_1997__9_1_51_0/}
}