A collaborative effort of the Networked Digital Library of Theses and Dissertations (NDLTD), OCLC, VTLS, and Scirus, the NDLTD Union Catalog contains more than one million records of electronic theses and dissertations. For students and researchers, the Union Catalog makes individual collections of NDLTD member institutions and consortia appear as one seamless digital library of electronic theses and dissertations.

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.

PLOS (Public Library of Science) is a nonprofit publisher and advocacy organization founded to accelerate progress in science and medicine by leading a transformation in research communication. PLOS entered the publishing arena in October 2003 with the launch of PLOS Biology, followed in October 2004 by PLOS Medicine. Today, it publishes a suite of influential Open Access journals across all areas of science and medicine. The Max Planck Society covers article-processing charges for Max Planck authors centrally. Further details are available on the MPDL website.

Various dictionaries are available.

The PrimateLit database provides bibliographic access to the scientific literature on nonhuman primates for the research and educational communities. Coverage of the database includes all publication categories (articles, books, abstracts, technical reports, dissertations, book chapters, etc.) and many subject areas (behavior, colony management, ecology, reproduction, field studies, disease models, veterinary science, psychology, physiology, pharmacology, evolution, taxonomy, developmental and molecular biology, genetics and zoogeography).

Project Gutenberg is a volunteer effort to digitize and archive cultural works. Founded in 1971 by Michael Hart, it is the oldest digital library. Project Gutenberg's mission is "To encourage the creation and distribution of eBooks".

A digital archive of life sciences journal literature managed by the National Center for Biotechnology Information (NCBI) at the U.S. National Library of Medicine (NLM).

Refubium is a service of the university library of the Freie Universität Berlin. As an institutional repository it collects documents, dissertations, postdoctoral theses, and research data.

MPG Resource Navigator is a web application to navigate through scientific information resources available to staff and guests of the Max Planck Society. It includes licensed databases, digital collections, and reference works. In addition, recommendable retrieval tools available on the web free of charge are part of the collection. Moreover, almost all Max Planck Institute library catalogs, as well as selected external ones, are accessible from here.

SocArXiv, open archive of the social sciences, provides a free, non-profit, open access platform for social scientists to upload working papers, preprints, and published papers, with the option to link data and code. SocArXiv is dedicated to opening up social science, to reach more people more effectively, to improve research, and build the future of scholarly communication.

SocioHub – ist das Portal des Fachinformationsdienstes Soziologie – es dient als zentrale Anlaufstelle für Ihre Literatursuche, Kommunikation und Information. Anstatt mehrere Webseiten besuchen zu müssen befinden sich hier alle Bereiche auf einer Plattform – direkt auf die Bedürfnisse der Soziologie zugeschnitten.

The German Socio-Economic Panel (SOEP) is a wide-ranging representative longitudinal study of private households, located at the German Institute for Economic Research, DIW Berlin. Every year, there were nearly 11,000 households, and about 30,000 persons sampled by the fieldwork organization Kantar Public Germany. The data provide information on all household members, consisting of Germans living in the Old and New German States, Foreigners, and recent Immigrants to Germany. The Panel was started in 1984. Some of the many topics include household composition, occupational biographies, employment, earnings, health and satisfaction indicators.

Springer Nature publishes the largest available collection of reproducible laboratory protocols and methods for the life sciences. The Experiments platform provides accees to the content from SpringerProtocols, Nature Methods, Nature Protocols and Protocol Exchange through a single easy-to-use platform, designed to save researchers' time.

SSOAR collects electronic full texts from the domain of the Social Sciences and makes these texts available according to the Berlin Declaration on Open Access to Scientific Knowledge.

The SSRN eLibrary consists of two parts: an Abstract Database containing abstracts on over 60,500 scholarly working papers and forthcoming papers and an Electronic Paper Collection currently containing over 38,400 downloadable fulltext documents in Adobe Acrobat pdf format. The eLibrary also includes the research papers of a number of Fee Based Partner Publications.

The department "Survey Data Curation", part of GESIS - Leibniz Institute for the Social Sciences, processes and prepares social science research data across a diverse range of data types to support research, especially in comparative perspectives across space and time. The curated data include long-term national (e.g., ALLBUS, GLES, Politbarometer, FReDA) and international (e.g., ISSP, EVS, CSES, Eurobarometer) survey programs with large user communities. The data are prepared for immediate re-use for research and teaching purposes. The department also offers services for linking surveys with geo-data and digital behavioral data.

The BSZ develops and maintains the SWB database in cooperation with 1,200 libraries in Baden-Württemberg, Pfalz, Saarland and Sachsen. The online catalog offers bibliographic data free of charge: Monographs, periodicals, articles, loose-leaf collections, off-prints, conference proceedings, university publications, reviews, abstracts, tables of contents, maps, music, audiovisual material, microforms, electronic resources (data media), online resources; scientific and popular literature from all subjects and in all languages from the 15th century to the present; scientific literature (according to the DFG special subject fields programme) from theology, ancient orient, art, music, archeology, law and criminology;

EVIFA, the portal of Social and Cultural Anthropology, offers anthropological and folkloristic information from one source. It gives a fast, comprehensive access to specific information for anthropological research, regardless of the where about.