@article{MOMA_1971__75_177541,
     author = {W. Ljunggren},
     title = {On the {Diophantine} {Equation} x2 + {D} = 4yq.},
     journal = {Monatshefte f\"ur Mathematik},
     pages = {136--143},
     publisher = {mathdoc},
     volume = {75},
     year = {1971},
     zbl = {0216.04003},
     url = {http://geodesic.mathdoc.fr/item/MOMA_1971__75_177541/}
}