[
  {
    "Title": "Missing DOI",
    "Year": 2024,
    "Abstract": "A record without DOI."
  },
  {
    "DOI": "10.1000/MISSINGTITLE",
    "Year": 2024,
    "Abstract": "A record without title."
  },
  {
    "DOI": "10.1000/MISSINGYEAR",
    "Title": "Missing year",
    "Abstract": "A record without year."
  },
  {
    "DOI": "10.1000/MISSINGABSTRACT",
    "Title": "Missing abstract",
    "Year": 2024
  },
  {
    "DOI": "",
    "Title": "Empty DOI",
    "Year": 2024,
    "Abstract": "Empty DOI should fail."
  },
  {
    "DOI": "10.1000/EMPTYTITLE",
    "Title": "",
    "Year": 2024,
    "Abstract": "Empty title should fail."
  },
  {
    "DOI": "10.1000/WHITESPACE",
    "Title": "   ",
    "Year": 2024,
    "Abstract": "Whitespace title is preserved and currently valid."
  },
  {
    "DOI": 123,
    "Title": "Non-string DOI",
    "Year": 2024,
    "Abstract": "DOI must be a string."
  },
  {
    "DOI": "10.1000/NONSTRINGTITLE",
    "Title": ["bad"],
    "Year": 2024,
    "Abstract": "Title must be a string."
  },
  {
    "DOI": "10.1000/NONSTRINGABSTRACT",
    "Title": "Non-string abstract",
    "Year": 2024,
    "Abstract": 42
  },
  {
    "DOI": "10.1000/STRINGYEAR",
    "Title": "String year",
    "Year": "2024",
    "Abstract": "Year must not be a string."
  },
  {
    "DOI": "10.1000/FLOATYEAR",
    "Title": "Float year",
    "Year": 2024.0,
    "Abstract": "Year must not be a float."
  },
  {
    "DOI": "10.1000/BOOLYEAR",
    "Title": "Boolean year",
    "Year": true,
    "Abstract": "Year must not be Boolean."
  },
  {
    "DOI": null,
    "Title": "Null DOI",
    "Year": 2024,
    "Abstract": "Null DOI should fail."
  },
  "not an object",
  {
    "DOI": "10.1000/DUPLICATE",
    "Title": "Duplicate one",
    "Year": 2024,
    "Abstract": "First duplicate."
  },
  {
    "DOI": "10.1000/DUPLICATE",
    "Title": "Duplicate two",
    "Year": 2025,
    "Abstract": "Second duplicate."
  },
  {
    "DOI": "10.1000/EXTRA",
    "Title": "Unexpected field",
    "Year": 2025,
    "Abstract": "Extra fields are rejected for MVP.",
    "Journal": "Example"
  }
]