Qatar Airways
http://www.qatarairways.com/global/en/offers/travel-festival-treasure-hunt.pages
http://www.flyertalk.com/forum/qatar-airways-privilege-club/1787777-treasure-hunt-promo-24.html
http://travelfree.info/2017/01/qatar-airways-treasure-hunt-travel-for-almost-free/
https://www.fly4free.pl/forum/zloty-bilet-od-qatar-airways,232,99790?start=340