Crossref Lookup Skill

This skill provides Python scripts and reference documentation for retrieving academic publication metadata using the Crossref REST API.

Quick Start

Unified Citation Lookup (NEW!)

Use scripts/citation_lookup.py for the easiest way to get both APA7 and BibTeX citations:

python scripts/citation_lookup.py bib.doi == 10.1038/s41586-025-09663-y
python scripts/citation_lookup.py bib.doi == https://doi.org/10.1038/s41586-025-09663-y
python scripts/citation_lookup.py 10.1038/nature12373
python scripts/citation_lookup.py https://doi.org/10.1038/nature12373

This command will:

• Look up the publication in Crossref
• Display complete publication information
• Generate APA 7th edition citation
• Generate BibTeX entry
• Save both citations to files automatically

Look Up by DOI

Use scripts/doi_lookup.py to get complete metadata for a publication:

python scripts/doi_lookup.py 10.1038/nature12373
python scripts/doi_lookup.py "10.1371/journal.pone.0161344"

Search Publications

Use scripts/search_works.py to search for academic works:

python scripts/search_works.py "machine learning" --rows 10
python scripts/search_works.py "climate change" --filter "from-pub-date:2020"

Search by Author

Use scripts/search_by_author.py to find publications by specific authors:

python scripts/search_by_author.py "Jane Smith"
python scripts/search_by_author.py "Einstein" --rows 20

Generate APA7 Citation

Use scripts/generate_apa7_citation.py to create citations from DOIs:

python scripts/generate_apa7_citation.py 10.1038/nature12373

Generate BibTeX

Use scripts/generate_bibtex.py to create reference manager entries:

python scripts/generate_bibtex.py 10.1038/nature12373

Get Journal Information

Use scripts/journal_lookup.py to retrieve journal metadata by ISSN:

python scripts/journal_lookup.py 0028-0836
python scripts/journal_lookup.py "1476-4687"

Script Reference

citation_lookup.py (UNIFIED TOOL)

Purpose: All-in-one DOI lookup with APA7 and BibTeX generation

Usage: python scripts/citation_lookup.py [bib.doi ==] <doi>

Examples:

python scripts/citation_lookup.py bib.doi == 10.1038/s41586-025-09663-y
python scripts/citation_lookup.py bib.doi == https://doi.org/10.1038/s41586-025-09663-y
python scripts/citation_lookup.py 10.1038/nature12373
python scripts/citation_lookup.py https://doi.org/10.1038/nature12373

Returns:

• Complete publication information
• APA 7th edition citation (printed and saved to file)
• BibTeX entry (printed and saved to .bib file)
• JSON output with all data

Files Created:

• <doi>_apa7.txt - APA citation with metadata
• <doi>.bib - BibTeX entry ready for Zotero/LaTeX

Special Format: Supports bib.doi == <doi> format for convenience

Accepts: DOI with or without URL prefix (https://doi.org/)

doi_lookup.py

Purpose: Retrieve complete metadata for a publication by DOI

Usage: python scripts/doi_lookup.py <doi>

Returns: JSON with full publication metadata including title, authors, journal, dates, references, and more

Accepts: Any valid DOI (with or without the "https://doi.org/" prefix)

search_works.py

Purpose: Search Crossref database for publications

Usage: python scripts/search_works.py "<query>" [--rows N] [--filter "filter_params"]

Returns: List of matching works with key metadata

Query Tips:

• Plain text searches across titles, abstracts, and full text
• Use --filter for advanced filtering (date ranges, publication types, etc.)
• Use --rows to control number of results (default: 10)

search_by_author.py

Purpose: Find publications by author name

Usage: python scripts/search_by_author.py "<author_name>" [--rows N]

Returns: Publications authored by the specified person

Note: Searches author fields in Crossref metadata

generate_apa7_citation.py

Purpose: Generate APA 7th edition citations from DOIs

Usage: python scripts/generate_apa7_citation.py <doi>

Returns: Formatted APA7 citation with structured data

Formats: Journal articles, books, conference papers, and more

generate_bibtex.py

Purpose: Generate Zotero-compatible BibTeX entries from DOIs

Usage: python scripts/generate_bibtex.py <doi>

Returns: Complete BibTeX entry with all available fields

Entry Types: @article, @book, @inproceedings, etc.

journal_lookup.py

Purpose: Get journal information by ISSN

Usage: python scripts/journal_lookup.py <issn>

Returns: Journal title, publisher, subjects, and other metadata

Accepts: ISSN (print or electronic)

Advanced Usage

For detailed API documentation and advanced features, read:

• references/api_reference.md - Complete Crossref API documentation
• references/response_schemas.md - JSON response structure examples
• references/citation_formats.md - Citation format guide with examples
• references/filters_guide.md - Advanced search filters and parameters

These references provide information about:

• All available API endpoints
• Query parameters and filters
• Rate limiting and etiquette
• Response field definitions
• Citation formatting rules
• Advanced search techniques

Dependencies

All scripts require the requests library:

pip install requests --break-system-packages

Best Practices

1. Use polite pool - Always include a mailto parameter in API requests for better rate limits
2. Respect rate limits - Free tier: 50 requests/second, Polite pool: higher limits
3. Handle errors gracefully - DOIs may not exist, API may be slow
4. Use appropriate timeouts - All scripts use 15-second timeouts for reliability
5. Cache results when making multiple requests for the same data
6. Read references for advanced filtering and search techniques
7. Verify citations - Always check accuracy before using in publications

API Etiquette

The Crossref API is free but follows an etiquette policy:

• Include your email in requests (mailto parameter) for better service
• Don't make excessive requests
• Cache responses when possible
• Use specific queries rather than broad searches
• Be a good API citizen!