Serbian, French and Italian troops push back the Bulgarians. Bulgarian troops trying to head west through Kosturino Pass were bombarded by airplanes.
Editors. "Allied break-through in Bulgaria". The Literary Encyclopedia. First published 01 March 2010; last revised 30 November -1.
[http://www.litencyc.com/php/stopics.php?rec=true&UID=12595, accessed 25 April 2015.]