Supported Query Parameters
Query Constraints
What fields are available for querying (e.g., DOI, ISSN, etc.)? Some constraints apply to specific APIs but not all. We represent this as follows:
- M: metadata API
- M2: meta/v2 API
- O: openaccess API
- F: Full Text API
| Constraint | Description | Applies to collection | Basic Plan* | Premium Plan* |
|---|---|---|---|---|
| doi:* | limit to a single Digital Object Identifier | M,O,M2,F |  | |
| doi:* | query multiple Digital Object Identifiers | M,O,M2,F | | |
| subject: | limit to the specified subject collection | M,O,M2,F | | |
| subject: | limit to the specified subject collection | M,O,M2,F | | |
| keyword: | limit to articles tagged with a keyword | M,O,M2,F | | |
| language: | limit to articles from a particular language | M,O,M2,F | | |
| pub: | limit to articles from a particular publication | M,O,M2,F | | |
| year: | limit to articles/chapters published in a particular year | M,O,M2,F | | |
| onlinedate: | limit to date that an article appeared online | M,O,M2,F | | |
| onlinedate(from/to): | limit to date range that an article appeared online, using onlinedatefrom, onlinedateto | M,O,M2,F | | |
| date(from/to): | limit to date range that an article was published, using datefrom, dateto (useful for older content where onlinedate might not exist) | M,O,M2,F | | |
| dateloaded: | limit to date that an article appeared in the database | M,O,M2,F | | |
| dateloaded(from/to): | limit to date range where loaded to database | M,O,M2,F | | |
| country: | limit to articles authored in a particular country | M,O,M2,F | | |
| isbn: | limit to a single International Standard Book Number | M,O,M2,F | | |
| issn: | limit to a single International Standard Serial Number | M,O,M2,F | | |
| journalid: | limit articles to a single Journal id | M,O,M2,F | | |
| topicalcollection: | limit content to a single toplical collection | M,M2,F | | |
| journalonlinefirst:true | limit articles to Online first | M,O,M2,F | | |
| date: | limit to documents published on a particular date {yyyy - mm - dd} | M,O,M2,F | | |
| issuetype | limit content to a issuetype | M,M2,F | | |
| issue | limit articles to a issue for journal | M,O,M2,F | | |
| volume | limit articles to a volume for journal | M,O,M2,F | | |
| type: | limit to either Book or Journal content {(Book, Journal)} | M,O,M2,F | | |
| ContainsElements: | limit to content containing a specific item | M,O,M2,F | | |
| excludeElements | [parameter] to exclude specific field from result | O,F | | |
| Exclude:Bibliography | do not search through bibliography/references; useful for finding terms that appear in the text only | M,O,M2,F | | |
| grid: | Global Research Identifier Database, providing unique identifiers for research organizations. | M,O,M2,F | | |
| orcid: | global identifier for specific author | M,O,M2,F | | |
| bookdoi: | limit to chapters from a specific BookDOI | M,O,M2,F | | |
| latest issue | limit to articles from the latest issue of the journal available in the database. | M,M2,F | | |
| earliest issue | limit to articles from the earliest issue of the journal available in the database. | M,M2,F | | |
| openaccess:true | limit to only Open Access content | M2,F | | |
| free:true | limit to only Free content (different from OA) | M,M2,F | |
"Contains" Constraints
When a "contains" constraint is applied, the response will return documents in which the specified argument appears anywhere within the relevant element.
The API currently supports the following types of "contains" constraints:
| Constraint | Description | Applies to collection | Basic Plan* | Premium Plan* |
|---|---|---|---|---|
| empty | A word or phrase that appears among the constraints but is not preceded by a constraint value will be treated as the argument of the "empty constraint" (i.e., a text/string search). Requests of this type will locate documents that contain the specified word or phrase in any element. | M,O,M2,F | | |
| title: | Locate documents containing a word or phrase in the "article/chapter title" element | M,O,M2,F | | |
| orgname: | Locate documents containing a word or phrase in the "organization name" element | M,O,M2,F | | |
| journal: | Locate documents containing a word or phrase in the "journal title" element | M,O,M2,F | | |
| book: | Locate documents containing a word or phrase in the "book title" element | M,O,M2,F | | |
| name: | Locate documents containing a word or phrase in the "author name" element | M,O,M2,F | |