@article{ELMA_1967__22_140856,
     author = {Edgar Karst},
     title = {The {Congruence} 2p-1 ...1 (mod p2) and {Quadratic} {Forms} with {High} {Density} of {Primes.}},
     journal = {Elemente der Mathematik},
     pages = {85--88},
     publisher = {mathdoc},
     volume = {22},
     year = {1967},
     zbl = {0154.30005},
     url = {http://geodesic.mathdoc.fr/item/ELMA_1967__22_140856/}
}