{
  "title": "Seven scalar two-point distributions from one normalized mode expansion",
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  "references": [
    {
      "citation": "Hollands, Stefan, and Robert M. Wald. Quantum Fields in Curved Spacetime. Physics Reports 574 (2015): 1-35.",
      "doi": "https://doi.org/10.1016/j.physrep.2015.02.001",
      "open_pdf": "https://arxiv.org/pdf/1401.2026v2",
      "locator": "2014 arXiv v2 preprint: section 2.1, pp. 9–14. Linear free-field algebra and state dependence; signs and support are derived using the page conventions.",
      "used_for": "Free-field commutator, causal propagator, state dependence, and algebraic scope. No graphical material was used."
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      "citation": "Schwartz, Matthew D. Quantum Field Theory and the Standard Model. Cambridge University Press, 2014.",
      "doi": "https://doi.org/10.1017/9781139540940",
      "locator": "Section 6.2, printed pp. 75-77, and Sections 14.3-14.4, printed pp. 261-266",
      "used_for": "Vacuum contractions, time ordering, contact-term normalization, pole contour, and source convention. No graphical material was used."
    },
    {
      "citation": "Weinberg, Steven. The Quantum Theory of Fields, Volume I: Foundations. Cambridge University Press, 1995.",
      "doi": "https://doi.org/10.1017/CBO9781139644167",
      "locator": "Section 6.2, printed pp. 274-277",
      "used_for": "Convention-translated structural and pole-placement checks. No graphical material was used."
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