Glad you asked! Documentation for the shared schema is here: https://unpaywall.org/data-format


And the field names are listed here so this article appears when you search for them:


best_oa_location

data_standard

doi

doi_url

endpoint_id

evidence

first_oa_location

genre

has_repository_copy

host_type

is_best

is_oa

is_paratext

journal_is_in_doaj

journal_is_oa

journal_issn_l

journal_issns

journal_name

license

oa_date

oa_locations

oa_locations_embargoed

oa_status

pmh_id

published_date

publisher

repository_institution

title

updated

url

url_for_landing_page

url_for_pdf

version

year

z_authors