Editors. "German Protestant princes present their grievances to Emperor Rudolf II". The Literary Encyclopedia. First published 01 February 2011
[http://www.litencyc.com/php/stopics.php?rec=true&UID=15410, accessed 24 May 2013.]
Holy Roman Emperor Rudolf II receives a list of grievances of the German Protestant princes, presented to him by Christian I of Saxony and the Elector John Casimir of the Palatinate.