@article{10_4064_aa146_4_1,
     author = {R. Clement Fern\'andez and J. M. Echarri Hern\'andez and E. J. G\'omez Ayala},
     title = {A geometric proof of {Kummer's} reciprocity law
 for seventh powers},
     journal = {Acta Arithmetica},
     pages = {299--318},
     publisher = {mathdoc},
     volume = {146},
     number = {4},
     year = {2011},
     doi = {10.4064/aa146-4-1},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/aa146-4-1/}
}