The positions of the Bulgarian army in the area of Doiran.
Looking up "P" ridge from Troupel
FALLS, Cyril Bentham. Military Operations Macedonia from the outbreak of war to the spring of 1917. [... From the spring of 1917 to the end of the war.], τ. Ι-ΙΙ, Λονδίνο, HMSO, 1933-35.
Hellenic Library - Alexander S. Onassis Public Benefit Foundation