Question: What is the code, defined by International Civil Aviation Organization, for Ridali Airfield?

Context paragraphs:
United Nations Security Council Resolution 1067: United Nations Security Council resolution 1067, adopted on 26 July 1996, after noting various statements and resolutions by the President of the Security Council and International Civil Aviation Organization (ICAO) deploring the shooting down of two civilian aircraft by the Cuban Air Force on 24 February 1996, the Council called on Cuba to comply with international obligations relating to aviation, particularly the Convention on International Civil Aviation.

Civil Aviation Authority, Bangladesh: Civil Aviation Authority, Bangladesh (CAAB) (Bengali: বেসামরিক বিমান চলাচল কর্তৃপক্ষ ) functions as the regulatory body for all aviation related activities in Bangladesh.  It is the national aviation authority operating under the Ministry of Civil Aviation & Tourism.  All nine operational airports (three international and six domestic) are operated by the CAAB.  A member of International Civil Aviation Organization, it has signed bilateral air transport agreement with 52 states.  It is headquartered in Kurmitola, Dhaka.

ICAO airport code: The ICAO ( , ) airport code or location indicator is a four-letter code designating aerodromes around the world.  These codes are defined by the International Civil Aviation Organization, and published in ICAO Document 7910: "Location Indicators" are used by air traffic control and airline operations such as flight planning.

Somali Civil Aviation Authority: The Somali Civil Aviation and Meteorology Authority (SCAMA) is the national civil aviation authority body of Somalia.  Based at the Aden Abdulle International Airport in the capital Mogadishu, it is under the aegis of the federal Ministry of Air and Land Transport.  In 2012, the ministry along with the Somali Civil Aviation Steering Committee set a three-year window for reconstruction of the national civil aviation capacity.  After a long period of management by the Civil Aviation Caretaker Authority for Somalia (CACAS), SCAMA in conjunction with the International Civil Aviation Organization also finalized a process in 2014 to transfer control of Somalia's airspace to the new Air Space Management Centre in the capital.

Civil Aviation Authority of Fiji: The Civil Aviation Authority of Fiji (CAAF) is the national aviation authority in the Republic of Fiji and is responsible for discharging functions on behalf of the Government of Fiji under the States responsibility to the Convention on International Civil Aviation, also known as the Chicago Convention on International Civil Aviation Organization (ICAO).  CAAF regulates the activities of airport operators, air traffic control and air navigation service providers, airline operators, pilots and air traffic controllers, aircraft engineers, technicians, airports, airline contracting organisations and international air cargo operators in Fiji.

Civil aviation: Civil aviation is one of two major categories of flying, representing all non-military aviation, both private and commercial.  Most of the countries in the world are members of the International Civil Aviation Organization (ICAO) and work together to establish common standards and recommended practices for civil aviation through that agency.

Lahe, Põlva County: Ridali Airfield (ICAO: EERI) is located in Lahe.

Ridali Airfield: Ridali Airfield (ICAO: EERI) ; Estonian: "Ridali lennuväli" ) is an airfield in Estonia, about 10 km north of Võru in the vicinity of Ridali - a place known for its beautiful scenery, abundance of lakes, fields and forests, giving glider pilots many visual reference points to navigate by.  The airfield was used during World War II, in the early 1960s it started serving glider pilots.  The first gliders to fly in Ridali were Soviet KAI-12's (improved design from the Czech LF-109).  The only way to launch gliders was by using the Czech winch "Herkules".  By 1968, the club already had two KAI-12's, three Blaníks, two towing winches and a Yak-12 for aerotows.

Civil Aviation Authority of Kosovo: Civil Aviation Authority of the Republic of Kosovo or CAAK (Albanian: "Autoriteti i Aviacionit Civil" ; Serbian: Autoritet Civilnog Vazduhoplovstva ) was established under Law No. 03/L-051 on Civil Aviation as an independent civil aviation regulatory agency.  CAAK is responsible for the regulation of civil aviation safety and the economic regulation of airports and air navigation services in the Republic of Kosovo.  Civil Aviation activities in Kosovo air space are carried out in accordance with the provisions of the Law on Civil Aviation, the Convention on International Civil Aviation of 7 December 1944, and the Agreement on the Establishment of a European Common Aviation Area.

Signal square: A signal square is an aerodrome equipment internationally defined at the annex 14 of the Convention on International Civil Aviation by the International Civil Aviation Organization.

Supporting paragraphs: Lahe, Põlva County ICAO airport code
Answer: EERI