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@book{oai:export,
@kein reference type{oai:export,
author = {Ludwig von Graff},
title = {Monographie der Turbellarien - 2. Tricladida Terricola (Landplanarien)},
year = {1899},
publisher = {Engelmann},
url = { \url{http://edoc.hu-berlin.de/docviews/abstract.php?id=29023} },
url = { \url{urn:nbn:de:kobv:11-10089262} },
timestamp = {2013-05-22T14:46:51Z}
}