old_contents: """Some additional journal abbreviations which are not provided by Crossref."""
  
  JOURNAL_ABBRVS = {
      "American Journal of Mathematics": "Am. J. Math.",
      "American Journal of Physics": "Am. J. Phys",
      "Annals of Physics": "Ann. Phys.",
      "Communications in Mathematical Physics": "Commun. Math. Phys.",
      "Journal of Mathematical Physics": "J. Math. Phys.",
      "Journal of Statistical Physics": "J. Stat. Phys.",
      "Nature Physics": "Nat. Phys.",
      "Nuclear Physics B": "Nucl. Phys. B",
      "Physics Letters A": "Phys. Lett. A",
      "Physics Letters B": "Phys. Lett. B",
      "Journal of High Energy Physics": "J. High Energ. Phys."
  }
  
new_contents: """Some additional journal abbreviations which are not provided by Crossref."""
  
  JOURNAL_ABBRVS = {
      "American Journal of Mathematics": "Am. J. Math.",
      "American Journal of Physics": "Am. J. Phys",
      "Annals of Physics": "Ann. Phys.",
      "Communications in Mathematical Physics": "Commun. Math. Phys.",
      "Journal of Mathematical Physics": "J. Math. Phys.",
      "Journal of Statistical Physics": "J. Stat. Phys.",
      "Nature Physics": "Nat. Phys.",
      "Nuclear Physics B": "Nucl. Phys. B",
      "Physics Letters A": "Phys. Lett. A",
      "Physics Letters B": "Phys. Lett. B",
      "Journal of High Energy Physics": "J. High Energ. Phys.",
      "Journal of Magnetism and Magnetic Materials": "J. Magn. Magn. Mater.",
      "Nature Communications": "Nat. Commun.",
      "Scientific Reports": "Sci. Rep.",
      "Journal of Applied Physics": "J. Appl. Phys.",
      "Physics Reports": "Phys. Rep."
  }
  
subject: Add more journal abbreviations