J. Goldstone, 1961, Nuovo Cimento, 19, 154, 10.1007/BF02812722
J. Goldstone, 1962, Phys. Rev., 127, 965, 10.1103/PhysRev.127.965
P. W. Anderson, 1963, Phys. Rev., 130, 439, 10.1103/PhysRev.130.439
F. Englert, 1964, Phys. Rev. Letters, 13, 321, 10.1103/PhysRevLett.13.321
S. L. Glashow, 1961, Ann. Phys. (N.Y.), 15, 437, 10.1016/0003-4916(61)90193-2
S. Coleman, 1964, Phys. Rev., 134, B671, 10.1103/PhysRev.134.B671
Y. Nambu, 1963, Phys. Rev. Letters, 11, 42, 10.1103/PhysRevLett.11.42
L. M. Brown, 1964, Phys. Rev. Letters, 13, 42, 10.1103/PhysRevLett.13.42