Austro-Hungarian Invasion 1878: Stampless cover from Stolac to Graz endorsed "KK Feldpost" at left, sent by an Officer in 8/II Regiment, struck with "ETAPPEN-POSTAMT / No. 5" datestamp (Dec 19) in black. Reverse with "Zara" cds of transit (Dec 26) and Graz arrival (Dec 29). The Feldpost at Stolac opened on 26 August 1878. Slight trim to envelope at left but scarce. Ex collection Keith Tranmer.