@article{JEMS_2008_10_1_a5,
     author = {Koen Thas and Don B. Zagier},
     title = {Finite projective planes, {Fermat} curves, and {Gaussian} periods},
     journal = {Journal of the European Mathematical Society},
     pages = {173--190},
     publisher = {mathdoc},
     volume = {10},
     number = {1},
     year = {2008},
     doi = {10.4171/jems/107},
     url = {http://geodesic.mathdoc.fr/articles/10.4171/jems/107/}
}