Burg, David F. (2010). Almanac of World War I, L. Edward Purcell, University Press of Kentucky, გვ. 336. ISBN9780813137711. „7 December 1916 [...] Falkenhayn's Ninth Army turns to the north in hopes of capturing the oil fields and refineries at Ploesti, but Falkenhayn is too late: John Norton-Griffiths has done his work. The oil fields at Ploesti, Targoviste, and elsewhere are aflame and their refining facilities in ruins - a severe loss to the German war effort, as it will be months before production can be restored.“