@article{AIHPA_1975__22_2_123_0,
     author = {Chen, Etang},
     title = {On the duality of local observables},
     journal = {Annales de l'I.H.P. Physique th\'eorique},
     pages = {123--130},
     publisher = {Gauthier-Villars},
     volume = {22},
     number = {2},
     year = {1975},
     mrnumber = {398332},
     zbl = {0303.46059},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/AIHPA_1975__22_2_123_0/}
}