BookOfConcord.org
‍This site contains the text of the Book of Concord as well as many other texts and resources related to the history of its development and its ongoing significance for the Church today.

Digital Commons Network
‍The Digital Commons Network is a free, open-access platform that aggregates scholarly articles, dissertations, and other works from university and college digital repositories around the world. Curated by university librarians, it provides access to a vast collection of peer-reviewed and original research, with every item being full-text and available to readers without a paywall.

Directory of Open Access Journals (DOAJ)
‍The Directory of Open Access Journals (DOAJ) is a non-profit, community-curated online directory that indexes and provides access to high-quality, open access, peer-reviewed journals across all subjects and languages.

ERIC (Education Resources Information Center)
‍The ERIC (Education Resources Information Center) database is a U.S. Department of Education-sponsored online resource for education research and information, providing a searchable collection of bibliographic records and full-text documents. It is a comprehensive database for students, teachers, administrators, and researchers, covering a wide range of education topics from adult and higher education to science and social studies education. The database includes peer-reviewed journal articles, research papers, books, dissertations, and other materials like government reports and conference proceedings.

Google Scholar
‍Google Scholar is a free search engine from Google that indexes a vast range of academic and scholarly literature from various sources, including articles, books, theses, abstracts, and court opinions. It allows users to search for scholarly information across many disciplines, connecting them with research papers, journal articles, and other scholarly documents published by academic publishers, professional societies, and universities.

‍iDAI.bibliograpy/ZENON
‍iDAI.bibliography/ZENON is a massive online catalog and central directory of the libraries of the German Archaeological Institute (DAI). It is one of the world’s largest bibliographic resources for ancient studies, containing approximately 1.4 million entries for publications like books, journals, and reviews, and is now a part of the larger iDAI.world digital research landscape.

IMSLP/Petrucci Music Library
‍IMSLP/Petrucci Music Library is a crowdsourced online library of over 390,000 public domain music scores and recordings that can be viewed and downloaded for free. Known officially as the International Music Score Library Project, it aims to make sheet music accessible to everyone, and its comprehensive collection is a valuable resource for musicians, students, and researchers.

Index Theologicus
‍The Index Theologicus (IxTheo) is a free, open-access online bibliography and research service for theology and religious studies. Provided by the University of Tübingen Libraries and Faculties, it offers comprehensive, multilingual indexing of journal articles, books, book reviews, and other media from around the world. IxTheo aims to provide scholars with access to relevant academic literature across various confessions and time periods, emphasizing European scholarship and providing access to full texts when possible.

Perseus Digital Library
‍The Perseus Digital Library is a pioneering, free online collection of historical texts and images, founded by Tufts University in 1987, with a primary focus on the ancient Greco-Roman world but also encompassing materials on the Arabic, Germanic, Renaissance, and 19th-century American periods. It provides access to digitized texts, art and artifacts, and research tools, including dictionaries and commentaries, aiming to make humanity’s entire record accessible to everyone.

Project Gutenberg
‍Project Gutenberg is the oldest digital library, providing access to over 75,000 free ebooks, with a focus on older works whose U.S. copyright has expired.

Smithsonian Institution Research Information System (SIRIS)
‍The Smithsonian Institution Research Information System (SIRIS) is a comprehensive, integrated system that provides access to the research resources of the Smithsonian Institution’s libraries, archives, and museums. It functions as a central search and management system, supporting researchers by offering a gateway to the institution’s collections and related external resources. SIRIS includes a wide array of materials, such as archives, manuscripts, photographs, and art records.

Thesaurus Linguae Graecae
‍The Thesaurus Linguae Graecae (TLG) is a research center at the University of California, Irvine that maintains a comprehensive digital library of ancient Greek literature. It contains virtually all surviving texts from the classical period and many from the Byzantine and post-Byzantine eras, providing a searchable corpus for scholars and students. Access to the full corpus requires a subscription, but an abridged version is available to the public.

World History Encyclopedia
‍World History Encyclopedia is a free, non-profit online resource that provides high-quality, rigorously researched, and accessible historical content to improve historical literacy worldwide. The website offers a vast collection of articles, images, and videos created by historians and scholars, along with resources for students and teachers like lesson plans and study guides.