BASE is a multidisciplinary search engine for scholarly internet resources which have been harvested from several hundred scientific repositories. Some of the indexed resources in BASE are subject to license, while most material is free available ("open access").

The Staatsbibliothek zu Berlin - Preußischer Kulturbesitz (Berlin State Library - Prussian Cultural Heritage) acquires texts from all fields of knowledge in all languages, in every available form, from all epochs and all countries of the world - providing the materials are of interest for academic and research purposes. Current holdings and collections include printed works from many centuries, manuscripts, music autographs, maps, globes, atlases, newspapers and periodicals, various microformed materials, an increasing number of digitally presented texts as well as extensive databases.

BN-OPALE PLUS combines into one catalog the records for the printed, sound, audiovisual, and multimedia materials collected by the Bibliothèque nationale de France (BnF) from its beginnings to the present day. The BN-OPALE PLUS catalog contains records for: * Books and periodicals making up the heritage collections, stored in BnF's François-Mitterrand Library, * Microfiche and microfilm, mostly created from heritage materials, * A selection of books and periodicals from special departments, * Open-Access materials from all the BnF libraries, * Sound recordings, videos, multimedia, and electronic materials comprising the heritage collections * Printed material and periodicals digitized by BnF, mostly in image format, * Electronic periodicals of which BnF also has the printed version, * Still images digitized by BnF, * Special materials regarding performing arts (pamphlets, programs, manuscripts,...) and cinema (movie posters, photographs). In addition, this catalog offers authority records containing extensive information on access rights (intellectual property rights and copyrights, subject matter, certificates, brand names, and others).

The union catalog encompasses the holdings of the Bavarian State Library, of libraries of Bavarian Universities and Universities of Applied Sciences, of several regional libraries and of some institutions affiliated with churches or ministeries. Die Verbunddatenbank umfasst den Bestand der Bayerischen Staatsbibliothek, der Universitäts- und Fachhochschulbibliotheken, diverser staatlicher Regionalbibliotheken und einiger kirchlichen und ministeriellen Einrichtungen.

This catalogue records information in e-journals, e-books, databases, and printed material about themes in the field of the international law. Especially, a large part of the print collection of the Peace Palace Library is searchable through this catalogue. This collection consists of books and materials since 1913.

Copac exposes rare and unique research material by bringing together the catalogues of c.90 major UK and Irish libraries. In a single search you can discover the holdings of the UK’s national libraries (including the British Library), many University libraries, and specialist research libraries.

The catalog comprises the holdings of the locations Leipzig since 1913, Frankfurt am Main since 1945, the holdings of the Deutsches Musikarchiv since 1976, and archival papers of the Deutsches Exilarchiv 1933-1945 since 2005. The catalog covers monographs, journals, maps and atlases, music and sound storage media, and dissertations published in Germany since 1913 (in print or electronically), in addition, translations from German into other languages and foreign-language works related to Germanic culture (since 1941). -- Der Katalog umfasst die Bestände der Standorte Leipzig seit 1913, Frankfurt am Main seit 1945, die Bestände des Deutschen Musikarchivs seit 1976 und die Archivalien des Deutschen Exilarchivs 1933-1945 seit 2005. Der Katalog beinhaltet in Deutschland seit 1913 erschienene Monografien, Zeitschriften, Karten und Atlanten, Musikalien und Tonträger, Dissertationen und Habilitationsschriften in gedruckter oder elektronischer Form, außerdem Übersetzungen aus dem Deutschen in andere Sprachen und fremdsprachige Germanica (seit 1941).

GBV is the Common Library Network of the German Federal States Bremen, Hamburg, Mecklenburg-Vorpommern, Niedersachsen, Sachsen-Anhalt, Schleswig-Holstein and Thüringen. The head office of the GBV (VZG) is situated in Göttingen. The GBV has established a virtual library in form of the GBV Union Catalogue (GVK) combining the resources of all participating libraries and making them easily accessible to the public.

Bei GovData handelt es sich um ein Metadatenportal, über das Bund, Länder und Kommunen ihre Daten zugänglich machen. Zentraler Bestandteil von GovData ist ein Metadatenkatalog. Über die darin enthaltenen standardisierten Metadaten (einheitliche strukturierte Beschreibungen) sind die Daten einfach auffindbar und zugänglich. Die Daten selbst werden weiterhin von den Datenbereitstellern dezentral vorgehalten und gepflegt.

The union catalog lists the holdings of all scientific libraries in Hessen and Rheinhessen. Inter-library loan requests may be submitted.

This database of the European Union (EU) contains the complete EU related terminology in all 24 official languages of the EU. -- Diese Datenbank der Europäischen Union (EU) enthält die gesamte EU-bezogene Terminologie in allen 24 EU-Amtssprachen.

JournalTOCS is the largest, free collection of scholary journal Tables of Contents (TOCs): 29,639 journals including 12,153 selected Open Access journals and 11,312 Hybrid journals from 2930 publishers.

The Karlsruhe Virtual Catalogue (KVK) is a meta search engine which allows you to simultaneously access selected library and book trade catalogs worldwide. Altogether, these resources contain hundreds of millions of books, magazines and other media.

The KOBV-Index is a central database that is maintained and regularly updated at KOBV-Zentrale. Der KOBV-Index ist eine zentrale Datenbank, die in der KOBV-Zentrale gepflegt und regelmäßig aktualisiert wird.

The database KRIMDok online covers criminological literature and literature of sciences related to criminology (e.g. psychology). The literature referred is predominantly German-speaking and consists of independent and dependent writings (books or essays). -- Die Datenbank KRIMDok online weist kriminologische Literatur sowie Literatur der kriminologischen Bezugswissenschaften nach (z.B. Psychologie). Die nachgewiesene Literatur ist vorwiegend deutschsprachig und besteht aus selbständigen und unselbständigen Schriften (Bücher bzw. Aufsätze).

The Library of Congress Online Catalog is a database of books, serials, computer files, manuscripts, cartographic materials, music, sound recordings, and visual materials in the Library's collections.

The goal of OAIster is to create a collection of previously difficult-to-access, academically-oriented digital resources that is easily searchable by anyone.

Open Syllabus is a non-profit research organization that collects and analyzes millions of syllabi to support novel teaching and learning applications. Open Syllabus helps instructors develop classes, libraries manage collections, and presses develop books. It supports students and lifelong learners in their exploration of topics and fields. It creates incentives for faculty to improve teaching materials and to use open licenses. It supports work on aligning higher education with job market needs and on making student mobility easier. It also challenges faculty and universities to work together to steward this important data resource. Open Syllabus currently has a corpus of nine million English-language syllabi from 140 countries. It uses machine learning and other techniques to extract citations, dates, fields, and other metadata from these documents. The resulting data is made freely available via the Syllabus Explorer and for academic research. The project was founded at The American Assembly, a public policy institute associated with Columbia University. It has been independent since 2019. All of the syllabi in the current collection are English language documents – including from universities where English is not the primary teaching language.

The OSF Preprints search combines records from various preprint repositories, including arXiv, bioRxiv, Cogprints, PeerJ, PsyArXiv, RePEc and SocArXiv.