^The floral change in the tertiary of the Rhön mountains (Germany) by Dieter Hans Mai - Acta Paleobotanica 47(1): 135-143, 2007.
^Pliocene and Early Pleistocene carpological records of terrestrial plants from the southern border of the Po Plain (northern Italy) by Edoardo Martinetto, Giovanni Monegato, Andrea Irace and Elena Vassio - Review of Palaeobotany and Palynology 218(1) November 2014 by DOI: 10.1016/j.revpalbo.2014.10.007