Serapeum Multi-Catalog Bibliographic Search

Serapeum Multi-Catalog Bibliographic Search allows WordPress administrators and editors to consult national and international library catalogues in real time via the SRU (Search/Retrieve via URL) protocol.

Features include:
* Search supported library catalogs using Title, Author/Creator, and Year filters.
* Import records directly into WordPress as Draft Posts using native 2-column Gutenberg block layouts.
* Export search results to CSV or BibTeX (.bib) formats for integration with reference managers (Zotero, Mendeley, EndNote).
* Clean, single-file lightweight architecture with zero external PHP dependencies.

External services

Supported Catalogs:
* BnF – Bibliothèque nationale de France (France)
base_url: https://catalogue.bnf.fr/api/SRU
Documentation: https://api.bnf.fr/fr/api-sru-catalogue-general
Conditions & Lienses: https://www.bnf.fr/fr/conditions-de-reutilisations-des-donnees-de-la-bnf
* Hispana – Ministerio de Cultura y Deporte (Spain)
base_url: https://hispana.mcu.es/es/sru/sru.do
Documentation: https://hispana.mcu.es/en/estaticos/contenido.do?pagina=estaticos%2Fsru
Conditions: https://hispana.mcu.es/es/contenido/aviso-legal.do
Warning: The year field does not work if you select Hispana
* DNB – Deutsche Nationalbibliothek (Germany)
base_url: https://services.dnb.de/sru/dnb
Documentation & licenses: https://www.dnb.de/EN/Professionell/Metadatendienste/metadatendienste_node.html
* Library of Congress (USA)
base_url: http://lx2.loc.gov:210/lcdb
Documentation: https://www.loc.gov/standards/sru/sru-1-1.html
Privacy policy: https://www.loc.gov/legal/security-copyright-and-privacy/privacy-policy/

IMPORTANT NOTICE: Library of Congress Connection Limits (SRU/Z39.50)

Please be aware that remote catalog search and consultation via the Library
of Congress (USA) SRU/Z39.50 protocol requires network requests through a
non-standard port (Port 210).

Due to these technical constraints, service availability strictly depends on
your hosting environment:

• SHARED HOSTING (NOT WORKING):
  Major hosting providers systematically block outgoing traffic on Port 210
  on shared plans for security reasons. These restrictions cannot be modified.
  As a result, connection attempts to the Library of Congress will fail or time out.

• VPS, DEDICATED, OR CLOUD SERVERS (WORKING):
  The service is fully functional only if your application is hosted on a
  Virtual Private Server (VPS), dedicated server, or Cloud instance, where
  the system administrator has full control over the firewall and can open
  outgoing traffic on Port 210.

HOW TO RESOLVE THIS ISSUE:
If you are on shared hosting and cannot migrate to a dedicated environment,
please contact your hosting provider’s technical support. Request them to
explicitly open “outgoing Port 210 to host lx2.loc.gov”. If your provider
denies the request, you will need a VPS or dedicated server to use this feature.