Open Access für Monographien: Kleine Fortschritte auf einem schwierigen Weg (Open Access for Monographs: Small Steps along a difficult Path)

From Google's English: 

"​While a considerable proportion of journal articles are now available in open access, only a few scientific monographs are currently openly accessible. Recently, however, more activities have been started and a number of reports have been published. We spoke with Olaf Siegert about the state of open access for monographs and about the activities of libraries."