DigiZeitschriften is a digital library containing digitized back issues of core German research journals. At the moment the platform provides full-text access to more than 600 journals dating back to 1850. The archive content is edited on an ongoing basis. Any existing gaps will be filled and missing data steadily added. Users from the MPG have access to the complete journal collection, older public domain content is available free of charge to anyone.

Duncker & Humblot is a German producer of high-quality academic research and scholarly publications, especially in the fields of law and social science. The Duncker & Humblot eLibrary provides users from the Max Planck Society with access to following products: * e-book collections 2007-2010, containing about 900 e-books in the fields of law, economics, social sciences, history, politics, philosophy and literary studies. * e-book collection Economics 1996–2005, containing about 360 e-books * e-book collection 'Best of reprints' Economics and Finance 1875–1941, containing about 100 e-books The collection is continuously extended by single e-book acquisitions by MPG libraries.

Nomos eLibrary provides access to academic books and journals in the subject areas of law, political sciences, economics, media and communication sciences, history, sociology, education and cultural studies, European Union, health sciences. The book selection has been continuously extended through the acquisition of individual eBook packages by MPG libraries. From volume 2022 onwards, access is given to the complete Nomos eBook portfolio. Max Planck researchers can publish their scientific work with Nomos as a print and in parallel as an Open Access eBook in the Nomos eLibrary. Further details are available on the MPDL website.

Olms Online is an e-book portal providing access to following collections: * Reprints: About 400 volumes with a focus on German language and literature and on philosophy. Olms Online presents titles with additional information. These are reprints with new introductions, afterwords, notes or indexes added by the editors. * Frankfurt and Leipzig Book Fair Catalogues: Book-trade catalogues, generally referred to as book fair catalogues, offer a unique overview of German and European book production over a period of nearly 300 years (1594-1860).

The SpringerLink platform provides MPG staff with access to a huge collection of English and German eBooks from 2005 onwards, as well as the English and the German collection of the Springer Book Archive (1842-2004). In addition, the content of selected book series is available. Includes major reference works and dictionaries. Max Planck researchers who publish a monograph or edited volume with Springer Nature as an Open Access eBook receive a discount on the standard Book Publishing Charge. MPDL covers the costs remaining on a pro rata basis. Further details are available on the MPDL website.

Since the publication of its first installment in 1976 the Theologische Realenzyklopädie has provided a comprehensive account of the state of theological research. Some 2000 articles present a multitude of historical and theological data in their context of faith and thought, theology and religion. A multidisciplinary approach integrates into the theological account not only the disciplines of Old Testament and New Testament Studies, Church History, and Systematic and Practical Theology but also Judaic Studies, Religious Studies and Philosophy.