@article{10_4064_aa_14_4_347_355,
     author = {L. Mordell},
     title = {The {Diophantine} equation $x^4 + y^4 = 1$ in algebraic number fields},
     journal = {Acta Arithmetica},
     pages = {347--355},
     publisher = {mathdoc},
     volume = {14},
     number = {4},
     year = {1968},
     doi = {10.4064/aa-14-4-347-355},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/aa-14-4-347-355/}
}