Certificated
DOUBLETREE BY HILTON HOTEL İSTANBUL-OLD TOWN
DOUBLETREE BY HILTON İSTANBUL - PIYALEPAŞA
DOUBLETREE BY HILTON İSTANBUL AVCILAR
DOUBLETREE BY HILTON TRABZON
DOUBLTREE BY HILTON BODRUM IŞIL CLUB RESORT
ELITE WORLD BUSINESS
ELITE WORLD ISTANBUL
ERESIN HOTELS TOPKAPI
ESER PREMIUM HOTEL & SPA BÜYÜKÇEKMECE
EURO PARK HOTEL
FAIRMONT QASAR ISTANBUL
FOUR SEASONS HOTEL ISTANBUL AT THE BOSPHORUS
GOLDEN TULİP HOTEL BAYRAMPAŞA
GRAND CEVAHİR HOTEL VE KONGRE MERKEZİ
GRAND HYATT İSTANBUL
GRAND MAKEL HOTEL
HARRINGTON PARK RESORT
Hilton İstanbul Bomonti Hotel & Conference Center
Hilton İstanbul Bosphorus
HILTON ISTANBUL MASLAK
HOLIDAY INN ANKARA ÇUKURAMBAR
HOLIDAY INN ISTANBUL AIRPORT
HOLIDAY INN ISTANBUL CITY
HOLIDAY INN ISTANBUL SISLI
