10 Liters diesel fuel coupon

Yugoslavia's chronic fuel shortages of the early 1980s forced the federal government to introduce rationed fuel coupons as a stopgap against spiraling import costs and a hard-currency deficit that made petroleum purchasing increasingly untenable. Private motorists were allocated fixed monthly quotas, with these coupons distributed through local communes and redeemed at filling stations in lieu of cash payment for the metered amount.

The watermark is an unexpectedly serious security measure for what amounts to a rationing chit — counterfeiting of fuel coupons was a genuine enforcement problem during the period.