>>348
例えば、Gupta-Bleuler の補助条件について、以下の参考文献が全て有料で、無料では読めない
と思うんですが、違いますか？

http://www.physics.rutgers.edu/~zrwan/QED-historical/QED_Ref3.1.html

[1] S.N. Gupta: Theory of Longitudinal Photons in Quantum Electrodymanics, Proc. Phys. Soc. A63 (1950) 681.

[2] K. Bleuler: Eine neue Methode zur Behandlung der Longitudinalen und Skalaren Photonen, Helv. Phys. Acta. 23 (1950) 567.

[3] A.S. Wightmann and L. Garding: Fields as Operator-Valued Distributions in Relativistic Quantum Theory, Ark. f. Fis. 28 (1964) 129.

[4] P.M. Mathews, M. Seetharaman and M.T. Simon: Indecomposability of Poincare-group Representations over Massless Fields and the Quantization Problem for Electromagnetic Potentials, Phys. Rev. D9 (1974) 1706.

[5] K. Just: The Lorentz Condition in Quantum Theory, Nuovo Cimento 38 (1965) 400.

[6] K. Haller and L.F. Landovitz: Subsidiary Condition in Quantum Electrodynamics, Phys. Rev. 171 (1968) 1749.

[7] K. Haller and L.F. Landovitz: Equivalence of the Coulomb Gauge and the Reformulated Lorentz Gauge, Phys. Rev. 182 (1969) 1922.

[8] K. Haller and L.F. Landovitz: Renormalization Constants, Wave Functions, and Energy Shifts in the Coulomb and Lorentz Gauges, Phys. Rev. D2 (1970) 1498.

[9] S.N. Gupta: Comment on Quantum Electrodynamics, Phys. Rev. 180 (1969) 1601.

[10] S.P. Tomczak and K. Haller: The Generalized-Lorentz-gauge Description of Quantum Electrodynamics, Nuovo Cimento 8B (1972) 1.