Wightman, A. S. (1971). Troubles in the external field problelml for invariant wave equations. Gordon and Breach.
Dyfyniad Arddull ChicagoWightman, A S. Troubles in the External Field Problelml for Invariant Wave Equations. New York: Gordon and Breach, 1971.
Dyfyniad MLAWightman, A S. Troubles in the External Field Problelml for Invariant Wave Equations. Gordon and Breach, 1971.
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