An EF data file for a volume consists of volume-level metadata, and of the extracted feature data for each page in the volume, in JSON format. The volume-level metadata consists of both volume metadata (metadata about the volume) and extracted features metadata (metadata about the extracted features).
- schemaVersion: A version identifier for the format and structure of this metadata object.
- dateCreated: The time this metadata object was processed.
- title: Title of the given volume.
- pubDate: The publication year.
- language: Primary language of the given volume.
- htBibUrl: HT Bibliographic API call for the volume.
- handleUrl: The persistent identifier for the volume
- oclc: The array of OCLC number(s).
- imprint: The publication place, publisher, and publication date of the given volume.