Question: What republic in the South Caucasus region is Lankaran International Airport located?

Context paragraphs:
List of companies of Armenia: Armenia is a sovereign state in the South Caucasus region of Eurasia.  Located in Western Asia, on the Armenian Highland, it is bordered by Turkey to the west, Georgia to the north, the "de facto" independent Nagorno-Karabakh Republic and Azerbaijan to the east, and Iran and Azerbaijan's exclave of Nakhchivan to the south.

Caucasus University: Caucasus University is a privately held university in Georgia, Caucasus.  The university was established in 2004 on the foundation of Caucasus School of Business, which was established in 1998 in partnership with Georgia State University, Atlanta, USA, during the country's transitional period.  This was when Georgia was making the first attempts to move from a planned to free market economy.  Caucasus University has evolved and is now one of the most prominent higher education institutions in Georgia and the South Caucasus region.

Foreign relations of Artsakh: The Republic of Artsakh is a republic with limited recognition in the South Caucasus region of Eastern Europe.  Republic of Artsakh controls most of the territory of the former Nagorno-Karabakh Autonomous Oblast and some of the surrounding area.  It is recognized by only three other non-UN member states, Abkhazia, South Ossetia and Transnistria.  The rest of the international community recognizes Artsakh as part of Azerbaijan.  In November 2012, a member of Uruguay's foreign relations committee stated that his country could recognize Nagorno-Karabakh's independence.  In 2012, Armenia and Tuvalu established diplomatic relations and it was perceived that Tuvalu may recognize Nagorno Karabakh’s independence.  Also in 2012, the Parliament of New South Wales, an Australian state, called upon the Australian government to recognise Nagorno-Karabakh.  In September 2014, the Basque Parliament in Spain adopted a motion supporting Nagorno-Karabakh's right to self-determination.

Lankaran International Airport: Lankaran International Airport (Azerbaijani: "Lənkəran Hava Limanı" ) is an airport serving Lankaran, a city in Azerbaijan in the south-east of Azerbaijan.  Reconstruction of the Lankaran airport started in 2005 and finished in 2008, when the Lankaran airport received the status of an international airport.

Flag of the Republic of Artsakh: On June 2, 1992, the self-proclaimed Republic of Artsakh, a "de facto" independent republic claimed by Azerbaijan, in the South Caucasus region, adopted a flag derived from the flag of Armenia, with only a white pattern added.  A white, five-toothed, stepped pattern was added to the flag, beginning at the two verges of the flag's right side and meeting at a point equal to one-third of the distance from that side.  The white pattern symbolizes the current separation of Artsakh from Armenia proper and its aspiration for eventual union with "the Motherland."  This symbolizes the Armenian heritage, culture and population of the area, and represents Artsakh as a separated region of Armenia by the triangular shape and the zigzag cutting through the flag.  The white pattern on the flag is also similar to the designs used on rugs, a symbol of national identity.  The ratio of the flag's breadth to its length is 1:2, same as the Armenian Tricolor.

Armenia (disambiguation): Armenia (officially the Republic of Armenia) is a sovereign state in the South Caucasus region of Eurasia.

Armenian Soviet Socialist Republic: Armenia ( , ; Armenian: Հայաստան , tr.  "Hayastan", ] ; Russian: Армения ; "Armeniya"), officially the Armenian Soviet Socialist Republic; (Armenian SSR; Armenian: Հայկական Սովետական Սոցիալիստական Հանրապետություն "Haykakan Sovetakan Soc'ialistakan Hanrapetut'yun" ; Russian: Армя́нская Сове́тская Социалисти́ческая Респу́блика "Armyanskaya Sovetskaya Sotsialističeskaya Respublika"), also commonly referred to as Soviet Armenia was one of the constituent republics of the Soviet Union in December 1922 located in the South Caucasus region of Eurasia.  It was established in December 1920, when the Soviets took over control of the short-lived First Republic of Armenia and lasted until 1991.  It is sometimes called the Second Republic of Armenia, following the First Republic of Armenia's demise.

Caucasus Research Resource Centers: The Caucasus Research Resource Centers program (CRRC) is a network of training, research support and resource centers established in 2003 in the capital cities of Georgia, Armenia and Azerbaijan.  CRRC’s primary aim is to improve and progress social science research and public policy analysis in the South Caucasus region.

Armenia: Armenia ( , ; Armenian: Հայաստան , "Hayastan " , ] ), officially the Republic of Armenia (Armenian: Հայաստանի Հանրապետություն , "Hayastani Hanrapetut'yun " , ] ), is a sovereign state in the South Caucasus region of Eurasia.  Located in West Asia on the Armenian Highlands, it is bordered by Turkey to the west, Georgia to the north, the "de facto" independent Nagorno-Karabakh Republic and Azerbaijan to the east, and Iran and Azerbaijan's exclave of Nakhchivan to the south.  The Republic of Armenia constitutes only one-tenth of historical Armenia, most of the rest is currently occupied by Turkey.

Azerbaijan: Azerbaijan ( ; Azerbaijani: "Azərbaycan" , officially the Republic of Azerbaijan (Azerbaijani: "Azərbaycan Respublikası" )), is a country in the South Caucasus region, situated at the crossroads of Southwest Asia and Southeastern Europe.  It is bound by the Caspian Sea to the east, Russia to the north, Georgia to the northwest, Armenia to the west and Iran to the south.  The exclave of Nakhchivan is bound by Armenia to the north and east, Iran to the south and west, while having an 11 km border with Turkey in the north west.

Supporting paragraphs: Lankaran International Airport Azerbaijan
Answer: Azerbaijan