@article{Segal1969,
 author    = {Irving Segal},
 title     = {Nonlinear Functions of Weak Processes I},
 publisher = {Elsevier Science},
 journal   = {Journal of Functional Analysis},
 issn      = {0022-1236,1096-0783},
 date      = {1969},
 volume    = {4},
 number     = {3},
 pages     = {404--456},
}
@article{Segal1970,
 title     = {Nonlinear Functions of Weak Processes II},
 author    = {Irving Segal},
 publisher = {Elsevier Science},
 journal   = {Journal of Functional Analysis},
 issn      = {0022-1236,1096-0783},
 date      = {1970},
 volume    = {6},
 number     = {1},
 pages     = {29--75},
}
@article{Klein1973,
  title = {Renormalized products of the generalized free field and its derivatives},
  volume = {45},
  ISSN = {0030-8730},
  number = {1},
  journal = {Pacific Journal of Mathematics},
  publisher = {Mathematical Sciences Publishers},
  author = {Abel Klein},
  date = {1973-03},
  pages = {275--292}
}
@article{Baez1989,
  title = {Wick Products of the Free Bose Field},
  volume = {86},
  ISSN = {0022-1236},
  number = {2},
  journal = {Journal of Functional Analysis},
 publisher = {Elsevier Science},
 author    = {John C. Baez},
  date = {1989-10},
  pages = {211--225}
}
@article{Fewster1998,
 title     = {Bounds on negative energy densities in flat spacetime},
 author    = {C. J. Fewster and S. P. Eveson},
 publisher = {The American Physical Society},
 journal   = {Physical Review D},
 issn      = {1550-7998,1089-4918},
 date      = {1998},
 volume    = {58},
 number     = {8},
 pages     = {084010},
}