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2024 November 15

Research Integrity Roundtable 2024

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Dominika Tkaczyk
2024 November 06

How good is your matching?

In our previous blog post in this series, we explained why no metadata matching strategy can return perfect results. Thankfully, however, this does not mean that it’s impossible to know anything about the quality of matching. Indeed, we can (and should!) measure how close (or far) we are from achieving perfection with our matching. Read on to learn how this can be done! How about we start with a quiz? Imagine a database of scholarly metadata that needs to be enriched with identifiers, such as ORCIDs or ROR IDs.

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Kornelia Korzec
2024 October 28

Update on the Resourcing Crossref for Future Sustainability research

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Lucy Ofiesh
2024 September 24

Meet the candidates and vote in our 2024 Board elections

On behalf of the Nominating Committee, I’m pleased to share the slate of candidates for the 2024 board election. Each year we do an open call for board interest. This year, the Nominating Committee received 53 submissions from members worldwide to fill four open board seats. We maintain a balanced board of 8 large member seats and 8 small member seats. Size is determined based on the organization’s membership tier (small members fall in the $0-$1,650 tiers and large members in the $3,900 - $50,000 tiers).

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Documentation

Using HTTPS to query

Most queries sent to our XML API will use HTTPS. For HTTPS querying you need to add either your Crossref member account credentials or an email address in the query. Use a DOI-to-metadata query when you know the DOI and want to find its associated metadata.

HTTPS query examples

DOI-to-metadata query example 

https://doi.crossref.org/servlet/query?pid={email@address.com}&id=10.1577/H02-043

DOI-to-metadata query requesting UNIXSD results 

https://doi.crossref.org/servlet/query?pid={email@address.com}&format=unixsd**&id=10.1577/H02-043

DOI-to-metadata queries may also be supplied using this format 

https://doi.crossref.org/search/doi?pid={email@address.com}&doi=10.1577/H02-043

XML query 

https://doi.crossref.org/servlet/query?usr={email@address.com}&format=unixref&qdata=<?xml version="1.0"?><query_batch version="2.0"...

where:

  • usr or pid is your email address
  • format is the desired results format
  • qdata is the query data (XML is the recommended format)
  • id is a Crossref DOI

XML querying

An XML query must contain complete and valid query XML. Multiple queries may be included in a single XML file, but the <query> element is repeatable. For best results, do not exceed 5 queries per HTTPS XML query request.

Multiple queries in a single request 

https://doi.crossref.org/servlet/query?usr=username&pwd=password&qdata=<?xml version = "1.0" encoding="UTF-8"?>  
<query_batch xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" version="2.0" xmlns="http://www.crossref.org/qschema/2.0"  xsi:schemaLocation="http://www.crossref.org/qschema/2.0 http://www.crossref.org/qschema/crossref_query_input2.0.xsd"><head><email_address>support@crossref.org</email_address><doi_batch_id>ABC_123_fff</doi_batch_id> </head> <body> <query key="query1" enable-multiple-hits="true" forward-match="false"><issn match="optional">15360075</issn><journal_title match="exact">American Journal of Bioethics</journal_title><author match="fuzzy" search-all-authors="false">Agich</author><volume match="fuzzy">1</volume><issue>1</issue><first_page>50</first_page><year>2001</year><article_title>The Salience of Narrative for Bioethics</article_title></query><query key="query2" enable-multiple-hits="true"><unstructured_citation>Hungate, B. A., &amp; Hampton, H. M. (2012). Ecosystem services: Valuing ecosystems for climate. Nature Climate Change, 2(3), 151-152.</unstructured_citation></query></body></query_batch>

HTTPS XML query example 

https://doi.crossref.org/servlet/query?usr=email@address.com&qdata=<?xml version = "1.0" encoding="UTF-8"?>  
<query_batch xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" version="2.0" xmlns="http://www.crossref.org/qschema/2.0"  xsi:schemaLocation="http://www.crossref.org/qschema/2.0 http://www.crossref.org/qschema/crossref_query_input2.0.xsd"><head><email_address>support@crossref.org</email_address><doi_batch_id>ABC_123_fff</doi_batch_id> </head> <body> <query key="1178517" enable-multiple-hits="false" forward-match="false"><issn match="optional">15360075</issn><journal_title match="exact">American Journal of Bioethics</journal_title><author match="fuzzy" search-all-authors="false">Agich</author><volume match="fuzzy">1</volume><issue>1</issue><first_page>50</first_page><year>2001</year><article_title>The Salience of Narrative for Bioethics</article_title></query></body></query_batch>

HTTPS XML query with an unstructured (formatted) citation

Learn more about querying with an unstructured (formatted) citation

https://doi.crossref.org/servlet/query?usr=email@address.com&format=unixref&qdata=<?xml version = "1.0" encoding="UTF-8"?><query_batch xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" version="2.0" xmlns="http://www.crossref.org/qschema/2.0" xsi:schemaLocation="http://www.crossref.org/qschema/2.0 http://www.crossref.org/qschema/crossref_query_input2.0.xsd"><head><email_address>your@email.org</email_address><doi_batch_id>01032012</doi_batch_id></head><body><query key="q1" enable-multiple-hits="true"><unstructured_citation>Hungate, B. A., &amp; Hampton, H. M. (2012). Ecosystem services: Valuing ecosystems for climate. Nature Climate Change, 2(3), 151-152.</unstructured_citation></query></body></query_batch>

HTTPS XML query with URL encoding 

https://doi.crossref.org/servlet/query?usr=email@address.com&qdata=%3C?xml%20version=%221.0%22?%3E%3Cquery_batch%20version=%222.0%22%20xsi:schemaLocation=%22https://www.crossref.org/qschema/2.0%20https://www.crossref.org/qschema/crossref_query_input2.0.xsd%22%20xmlns=%22https://www.crossref.org/qschema/2.0%22%20xmlns:xsi=%22http://www.w3.org/2001/XMLSchema-instance%22%3E%3Chead%3E%3Cemail_address%3Esupport@crossref.org%3C/email_address%3E%3Cdoi_batch_id%3EABC_123_fff%3C/doi_batch_id%3E%20%3C/head%3E%20%3Cbody%3E%20%3Cquery%20key=%221178517%22%20enable-multiple-hits=%22false%22%20forward-match=%22false%22%3E%3Cissn%20match=%22optional%22%3E15360075%3Cissn%3Cjournal_title%20match=%22exact%22%3EAmerican%20Journal%20of%20Bioethics%3C/journal_title%3E%3Cauthor%20match=%22fuzzy%22%20search-all-authors=%22false%22%3EAgich%3C/author%3E%3Cvolume%20match=%22fuzzy%22%3E1%3C/volume%3E%3Cissue%3E1%3C/issue%3E%3Cfirst_page%3E50%3C/first_page%3E%3Cyear%3E2001%3C/year%3E%3Carticle_title%3EThe%20Salience%20of%20Narrative%20for%20Bioethics%3C/article_title%3E%3C/query%3E%3C/body%3E%3C/query_batch%

Note that some characters must be URL-encoded:

CharacterNameURL code
;Semi-colon%3B
/Slash, virgule, separatrix, or solidus%2F
?Question mark%3F
:Colon%3A
@At sign, arobase%40
=Equals sign%3D
&Ampersand%26
lfline feed%0A

Page owner: Patrick Polischuk   |   Last updated 2020-April-08