Kubikat is the collective catalog of four of the leading German scholarly research institutes in the field of art history * Kunsthistorisches Institut in Florence (Max-Planck-Institut) * Zentralinstitut für Kunstgeschichte in Munich - funded by the Bavarian Ministry of Sciences, Research and the Arts * Deutsches Forum für Kunstgeschichte (Centre allemand d'histoire de l'art) in Paris - funded by the Foundation of German Humanities Institutes Abroad (DGIA) * Bibliotheca Hertziana (Max Planck-Institut für Kunstgeschichte) in Rome The catalog project began in 1993 as a joint initiative of the institutes in Munich, Rome and Florence, supported by the German Research Foundation (DFG)

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.

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 Patrologia Latina Database is an electronic version of the first edition of Jacques-Paul Migne's Patrologia Latina, published between 1844 and 1855, and the four volumes of indexes published between 1862 and 1865. Patrologia Latina comprises the works of the Church Fathers from Tertullian in 200 AD to the death of Pope Innocent III in 1216. The complete Patrologia Latina is included with all prefatory material, original texts, critical apparatus and indexes. Migne's column numbers, essential references for scholars, are included.

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.