@article{MAN_1996__306_3_165460,
     author = {R. Elman and B. Jacob and J.K. Arason},
     title = {The {Witt} ring of an elliptic curve over a local field.},
     journal = {Mathematische Annalen},
     pages = {391--418},
     publisher = {mathdoc},
     volume = {306},
     number = {3},
     year = {1996},
     zbl = {0922.11037},
     url = {http://geodesic.mathdoc.fr/item/MAN_1996__306_3_165460/}
}