Dutch Ships and Sailors brings together four Dutch maritime historical datasets. The datasets are modeled as Linked Data, with internal and external links and a schema mapping...

The Open Economics project provides open content, data and code related to Economics. This site itself provides interfaces to some (though not all) of the Open Economics...

From wikipedia: The institute is one of the world's largest documentary- and research-centres for social history. Items in its custody include those relating to Karl Kautsky,...