Gustavus II of Sweden, who has been besieging the Polish-Lithuanian
city of Danzig, is forced to raise the siege.
Citation:
Editors. "Gustavus II of Sweden raises the siege of Danzig".
The Literary Encyclopedia. First published 01 February 2011
[http://www.litencyc.com/php/stopics.php?rec=true&UID=15969, accessed 23 May 2013.]