@article{JRAM_1975__272_151526,
     author = {Charles J. Parry},
     title = {Pure quartic number fields whose class numbers are even.},
     journal = {Journal f\"ur die reine und angewandte Mathematik},
     pages = {102--112},
     publisher = {mathdoc},
     volume = {272},
     year = {1975},
     zbl = {0312.12006},
     url = {http://geodesic.mathdoc.fr/item/JRAM_1975__272_151526/}
}