@article{Epstein1965,
  author       = {Epstein, H. and Glaser, V. and Jaffe, A.},
  title        = {Nonpositivity of the Energy Density in Quantized Field Theories},
  publisher    = {Società Italiana di Fisica},
  journaltitle = {Il Nuovo Cimento},
  volume       = {36},
  issue        = {3},
  date         = {1965},
  pages        = {1016--1022},
  issn         = {1827-6121},
  doi          = {10.1007/BF02749799},
  language     = {english},
}