Air Berlin

Air Berlin
IATA
AB
ICAO
BER
Callsign
AIR BERLIN
Founded 1978 (as Air Berlin USA)
Hubs
Focus cities
Frequent-flyer program topbonus
Alliance Oneworld (future)
Fleet size 151
Destinations 163
Company slogan Your Airline.
Headquarters Airport Bureau Center
Charlottenburg-Wilmersdorf,
Berlin, Germany
Key people
Revenue 3,723.6 million (2010)[1]
Website airberlin.com

Air Berlin PLC & Co. Luftverkehrs KG (stylized as airberlin or airberlin.com) is Germany's second largest airline, after Lufthansa, and Europe's sixth largest airline in terms of passengers.[2]

The airline operates an extensive network including holiday destinations in the Mediterranean region, the Canary Islands and North Africa as well as intercontinental destinations in Southeast Asia, the Caribbean and the Americas.

Air Berlin concentrates on serving major German and European cities to attract business traffic. A total of 23 German cities are served, more than any other airline. Its largest hub is Berlin-Tegel Airport,[3] followed by Düsseldorf Airport. Other important destinations are the focus cities Nuremberg Airport and Son Sant Joan Airport, Palma.

On 26 July 2010, the Oneworld airline alliance announced that Air Berlin had been invited to join.[4] Full membership is planned for the start of 2012.

The airline is headquartered at the Airport Bureau Center in Charlottenburg-Wilmersdorf, Berlin.[5] Air Berlin's parent company, airberlin group or Air Berlin PLC, is publicly traded (FSE: AB1, ISIN is GB00B128C026).[6]

In March 2011, it had 8,900 employees.[1] The airline (including subsidiaries) carried 33.6 million passengers in 2010.[7]

Contents

History

1978–1989: First years of air charter operations

In 1978, former Pan Am pilot Kim Lundgren formed Air Berlin as a US supplemental carrier non-scheduled US airline under the name Air Berlin, Inc. in Oregon, USA, trading as Air Berlin USA and headquartered in Miami, Florida.[8] That the airline was founded in the United States rather than in Germany was due to West Berlin's special legal status during the Cold War era; during that time, all air traffic to and from the city was restricted to airlines of the victorious powers of World War II. In addition, all flight-deck crew (pilots, flight engineers and navigators) on flights through the Allied air corridors had to be citizens of the United States, United Kingdom, France or the Soviet Union.[9]

Air Berlin's first revenue flight (from Berlin to Palma de Mallorca) took place on 28 April 1979, with its first aircraft being a Boeing 707–320, which had been acquired from TWA.[10] Operating from Berlin-Tegel Airport, the airline was assigned to fulfill lucrative charter contracts operating a series of short to medium-haul IT charter flights to the Mediterranean and the Canary Islands on behalf of Berliner Flug Ring, at that time West Berlin's leading package tour operator.[11] Air Berlin had taken over this contract from Aeroamerica, another US supplemental carrier, which was based at Berlin Tegel from 1974 to 1979.[11] Additionally, Air Berlin operated weekly scheduled service from Tegel via Brussels to Orlando, during a brief period in the early 1980s.[12]

In the spring of 1981, Air Berlin's original two Boeing 707 aircraft were replaced by the more modern Boeing 737–200 Adv type, which was more appropriate for the airline's IT operations from Berlin to the Mediterranean region, especially to Majorca (where it is now the largest airline operating there).[13]

In 1985, Air Berlin moved its headquarteres to Berlin.[14] Air Berlin transitioned to a fleet entirely composed of brand-new Boeing 737-300 and 737–400 aircraft during the late 1980s.[15] This coincided with the introduction of a new livery, which remained relatively unchanged until 2007.[15]

1990–1999: Growth after German reunification

On 2 October 1990, the eve of Germany's reunification (which led to the end of Berlin's special status), the airline was renamed Air Berlin, and German investors acquired a majority stake in the company with Joachim Hunold, a former LTU manager, becoming CEO, a position he held until 2011. Some time later, on 16 April 1991, the airline was re-registered under German law and renamed Air Berlin GmbH & Co. Luftverkehrs KG.[16][16][17] Air Berlin joined IATA, the company also moved away from charters and towards scheduled flights, including important European business centres (which had been served since 1997).

2000–2006: Becoming Germany’s second largest airline

In November 2001, when taking delivery of a brand new Boeing 737–800 fitted with winglets, Air Berlin managed to set a record. The aircraft with the registration code D-ABBC flew the 8,345 kilometres non-stop from Seattle (BFI), USA to Berlin (TXL), Germany in 9 hours 10 minutes.

In January 2004, Air Berlin announced it would cooperate with Niki, a Vienna-based airline.[16] As part of the deal, Air Berlin took a 24% stake in Niki.

In 2005, a partnership agreement with Germania was signed. It saw Air Berlin leasing some of Germania's aircraft and crew, and Germania became almost exclusively a charter airline. Germania was to have been associated with Air Berlin under a management contract. However, the contract was not signed. At the beginning of March 2008 Germania’s joint owners could not reach agreement about the takeover by Air Berlin, so Germania remained an independent airline.

In 2006, Air Berlin successfully completed an initial public offering (IPO) on the Frankfurt Stock Exchange. Originally scheduled for 5 May 2006, it was postponed until 11 May 2006. The company cited recent rises in fuel costs and other market pressures leading to limited of investor demand and reduced the initial share-price range from 15.0–17.5 euros to 11.5–14.5 euros and the stock opened at €12.0, selling a total of 42.5 million shares. Of these, 19.6 million were new shares increasing capital in the company, and the remainder to repay loans extended by the original shareholders and invested in the company earlier in 2006. After the IPO, the company claimed to have over 400 million euros in cash to fund further expansion, including aircraft purchases.[18]

In August 2006, Air Berlin announced that it had acquired 100% of the shares in German domestic airline dba.[19] Flight operations at dba were continued as a fully owned subsidiary of Air Berlin until 14 November 2008, when the dba brand was discontinued due to staff strikes. (dba staff were subsequently offered positions with Air Berlin).

On 28 November 2006, aircraft manufacturer Boeing announced an Air Berlin order of 60 Boeing 737-800 aircraft, as well as for 15 aircraft of the smaller Boeing 737-700 variant. The combined value of these 75 airplanes would be 5.1 billion dollars at then list prices. Delivery started in 2007.[20] All of these aircraft will be equipped with blended winglets, which significantly improve fuel efficiency.

2007–2009: Takeovers and expansion

In March 2007, Air Berlin took over German leisure airline LTU, thereby gaining access to the long-haul market and becoming the fourth largest airline group in Europe in terms of passenger traffic. This deal lead to the introduction of Airbus A321 and Airbus A330 aircraft into the Air Berlin fleet. The merger of the LTU operations, aircraft and crew was completed on 1 May 2009, when the LTU brand was dicontinued.

On 7 July 2007, Air Berlin announced an order for 25 modern Boeing 787–8 Dreamliner longhaul aircraft, with further options and purchase rights.[21] Three additional aircraft of this type will be leased from ILFC. Entry into service is projected for 2011.

On 21 August 2007, Air Berlin acquired a 49 percent shareholding in Swiss charter airline Belair, the remainder being owned by tour operator Hotelplan.[22] Following the deal, Belair's longhaul business was shut down, and the fleet replaced by Airbus A320 family aircraft operating scheduled flights on behalf of Air Berlin as well as charter flights for Hotelplan.

On 20 September 2007, Air Berlin announced it intended to buy its direct competitor Condor in a deal that saw Condor's owner, the Thomas Cook Group, taking a 30% stake in Air Berlin.[23] A variety of considerations, including the rapidly increasing price of jet fuel, led to the abandonment of the deal in July 2008.

In January 2008 Air Berlin introduced a new logo together with a new corporate design. The logo is a white oval shape on a red background (to suggest an aircraft window) where the letter “a” is depicted by a white circle and two white stylised wings. The Air Berlin text element is now in lower case and written as one word. Sometimes the slogan “Your Airline” also features as part of the logo.[24]

In June 2008, CEO Joachim Hunold caused a quarrel with the Catalan People, when he claimed [25] in an article included in Air Berlin's inflight magazine that the government of the Balearic Islands was trying to impose the use of Catalan onboard of Air Berlin flights from and to Majorca. He claimed that Air Berlin was an international airline and therefore would not have to use Catalan. Hunold went on to criticise the language policy in Catalonia and the Balearic Islands, claiming that at the time many children could not speak any Spanish.[26] The Balearic Islands' socialist President, Francesc Antich, explained that his government had simply sent a letter to encourage airlines operating in the Balearic Islands to include Catalan among the languages used for onboard announcements.[27] On 18 June of the same year, Air Berlin announced that it would reduce its long-haul services by 13 percent, as well as cut 10 percent of services on the domestic market in an effort to increase profitability.[28]

In January 2009 Air Berlin started a co-operation with Hainan Airlines, China’s fourth-largest airline. Both airlines offer jointly market flights between Berlin and Beijing. The code-share flights are sold on a reciprocal basis and operated under the relevant airline’s own flight number.[29]

At the end of March 2009, a strategic partnership agreement with TUI Travel was signed, which is based on a cross ownership of Air Berlin and its direct competitor TUIfly each purchases 19.9 percent of the other's shares.[30] Following this deal, Air Berlin took over all German domestic TUIfly routes, as well as those to Italy, Croatia and Austria. Also, all of Tuifly's Boeing 737-700 aircraft were merged into Air Berlin's fleet. Further route shifts will see TUIfly abandoning all scheduled flights and relying exclusively on the charter business.[31]

In March 2009 ESAS Holding bought approximately 15 per cent of the voting shares in Air Berlin PLC. The Federal Cartel Office in Bonn has notified Air Berlin PLC & Co. Luftverkehrs KG that it has no objections to the Turkish company ESAS Holding A.S. acquiring a stake in the airline.[32]

On 28 September 2009, Air Berlin announced it would cooperate with Pegasus Airlines, thus allowing its customers access to more destinations and flights to and within Turkey on a codeshare-like basis.[33]

In October 2009 Air Berlin entered into cooperation with Bangkok Airways. Air Berlin offers passengers the flights operated by Bangkok Airways under its own flight number.[34]

2010-2012: Further takeovers and alliances

Air Berlin Group
Company Interest
airberlin technik GmbH 100 %
Binoli Reiseplattform 049 %
Belair 100 %
Niki 49.9%

In April 2010 Air Berlin expanded its codeshare arrangements with Russia’s S7 Airlines. The strategic cooperation between Air Berlin and S7 Airlines had been in place since October 2008. New services include codeshare flights via Moscow to destinations such as Irkutsk, Perm and Rostov.[35]

In July 2010 Air Berlin PLC announced an increase in its shareholding in the Austrian airline Niki. Following the fulfilment of the required conditions, the agreements notarized on 17 February 2010 have been implemented. Air Berlin PLC & Co. Luftverkehrs KG indirectly acquired 25.9% of the shares in Niki Luftfahrt GmbH from the Privatstiftung Lauda (private Lauda foundation) and has thereby increased its current shareholding in Niki Luftfahrt GmbH from 24% to 49.9%. In connection with the increase of its shareholding, Air Berlin PLC & Co. Luftverkehrs KG will grant the private Lauda foundation a 40.5 million-euro loan. The private foundation has the option to repay the loan in three years with cash or through the transfer to the remaining 50.1% of Niki Luftfahrt GmbH´s shares.[36]

In July 2010, it was also announced that Air Berlin would be joining Oneworld, the global airline alliance.[37] Full membership is planned for the start of 2012.[38] In preparation for joining the alliance, Air Berlin has been offering flights under codeshare agreements with American Airlines and Finnair since its 2010/2011 winter schedule came into force. Its cooperation with American Airlines means that Air Berlin passengers gain access to the important American market whilst it also offers codeshare flights with Finnair to Helsinki and within Europe.[39]

Air Berlin PLC founded Follow Me Entertainment GmbH in September 2010 as a joint venture with kick-media ag. This joint venture company has been formed for the individual marketing of image and sound media, books, games as well as events, concerts, tournaments and sponsoring.[40]

The foundations were laid for the first maintenance hangar at Berlin Brandenburg Airport (BER) on 21 March 2011. Air Berlin, which will use the hangar together with Germania as from June 2012, has thus doubled the maintenance capacity of Air Berlin Technik at its Berlin site.[41]

On 1 April 2011 Air Berlin completed the full integration of LTU which it took over in August 2007. There is now only one flight schedule and all the technical services of the Air Berlin Group have been merged into a new company "airberlin technik GmbH".[42] Also in April 2011 Air Berlin underlined the importance of its Düsseldorf hub by creating a new position of "Regional Director North-Rhine Westphalia". With new routes, more frequent flights and additional long-haul flights, Air Berlin is expanding the flights it offers from Düsseldorf.[43]

On 15 June 2011, Air Berlin and British Airways reached a codeshare agreement covering selected flights within Europe, commencing from 5 July 2011. The agreement applies to flights to over 40 European destinations served by the two airlines.[44]

Corporate affairs

Key business trends

The key trends for Air Berlin over recent years are shown below (as at year ending 31 December):

2003 2004 2005 2006 2007 2008 2009 2010
Turnover (€m) 863 1,034 1,215 1,575 2,537 3,401 3,240 3,724
Profits (€m) 36.7 −2.9 −115.9 40.1 21.0 −75.0 −9.5 −97.2
Number of employees 1,956 2,146 2,764 4,108 8,360 8,311 8,278 8,900
Number of passengers (m) 10.0 12.1 17.5 19.7 27.9 28.6 27.9 33.6
Passenger load factor (%) 76.7 79.5 75.2 75.3 77.2 78.4 77.3 76.8
Number of aircraft (at year end) 46 47 79 117 124 125 152 169

Flight school

Air Berlin has been running its own pilot training scheme since 2007 in a joint venture with the TFC Käufer flight school. Trainees complete their commercial pilot training to the latest industry standards over a period of around 24 months. The Air Berlin flight school was the first flight school in Germany to be awarded a training licence by the German Department of Aviation for the new Multi-Crew Pilot Licence concept in February 2009.[45]

Technical services

Major shareholders
Share Shareholder
29.00 % Ethiad Airlines. (Abu Dhabi)
16.48 % ESAS Holding A.S. (Turkey)
7.51 % Hans-Joachim Knieps
6.85 % Leibniz-Service GmbH / TUI Travel PLC
5.74 % Ringerike GmbH & Co. Luftfahrtbeteiligung
Metolius Foundation
3.82 % Werner Huehn
3.70 % JPMorgan Chase & Co.
2.93 % Rudolf Schulte
2.93 % Severin Schulte
2.67 % Joachim Hunold, former CEO Air Berlin PLC
2.39 % Moab Investments Ltd.
1.58 % Johannes Zurnieden, Chairman Air Berlin PLC
1.40 % Heinz-Peter Schlüter
~ 40 % diversified holdings
as at: 30 September 2011[46]

airberlin technik, part of the airberlin group, is a certified EASA Part-145 maintenance organization with approximately 1200 employees providing services to both the aircraft operating within the airberlin group and customers throughout Europe. airberlin technik is recognized and approved by various National Airworthiness Authorities such as USA FAA-145, Canadian CAA-145, Aruba EASA-145, Federal Aviation Authority of Russia, GCAA, United Arab Emirates.[47]

Passenger services

In contrast to pure European low-cost carriers, Air Berlin offers free (at the point of consumption) in-flight snacks and drinks, as well as newspapers and magazines. Full hot meals are complimentary on long-haul flights. On all Air Berlin routes with a flight time of 60 minutes or longer, gourmet meals are offered, which are, according to the airline, created by chefs at "Sansibar", a famous restaurant on the island of Sylt. The airline also offers in-flight entertainment, assigned seating and guaranteed flight connections.[48] On flights operated by Airbus A330-200 aircraft, a dedicated business class section is offered.[49]

Frequent flyer programme

Like many other airlines, Air Berlin has a frequent flyer scheme. Air Berlin's frequent flyer program (called topbonus) is operated jointly with Niki. Points (“miles”) can be collected on all flights, and these can be redeemed later for free flights (award flights) or for an upgrade to business class. In addition to the “topbonus Card Classic” there are cards with Silver and Gold status. A Service Card and a Credit Card, for which a charge is made, are also available.

Destinations

The airline operates an extensive semi-low-cost network including intercontinental destinations in the United States, the Caribbean and the South East Asia as well as holiday destinations in the Mediterranean region, the Canary Islands and North Africa, with a total of 163 scheduled destinations in 39 countries.

Codeshare agreements

Air Berlin has codeshare agreements with the following airlines (as of 19 December 2011 (2011 -12-19)):

Fleet

Boeing 737-800 with winglets, in current colours.
Boeing 737-700 in a special Air Berlin–Boeing hybrid livery.

As of August 2011, the Air Berlin fleet consists of the following aircraft, with an average age of 5.9 years:[51]

Air Berlin fleet
Aircraft Total Orders Options Passengers Notes
C Y Total
Airbus A319-100 11 0 150 150 2 stored
Airbus A320-200 36 18 0 174 174 7 operated by Belair (Swiss registered, 1 stored)
Airbus A321-200 10 5 0 210 210
Airbus A330-200 12 24 279 303
Airbus A330-300 2 0 387 387
Boeing 737-700 26 8 0 144 144 10 operated by TUIfly (registrations D-AH_)
6 operated by Germania (registrations D-AGE_)
Boeing 737-800 39 48 0 186 186 4 operated by TUIfly (registrations D-AHF_)
Boeing 787-8 18 5 TBA 3 will be leased; entry into service: April 2014
Bombardier Dash 8 Q400 10 0 76 76 operated by LGW
Total 146 97 5

Fleet development

Over the years, Air Berlin operated the following aircraft types:[52]

Air Berlin fleet development
Aircraft Introduced Retired Notes
Airbus A319
2006
4 overwing window exits instead of the A319's usual 2
Airbus A320
2005
Airbus A321
2008
following the LTU fleet incorporation
Airbus A330-200
2008
following the LTU fleet incorporation
Airbus A330-300
2008
following the LTU fleet incorporation
BAe 146-200
2003
2004
leased from WDL Aviation
Boeing 707
1978
1981
Air Berlin USA
Boeing 737-200
1980
1986
Air Berlin USA
Boeing 737-300
1986
2007
1990
2010
Air Berlin USA
[]
Boeing 737-400
1990
2007
Boeing 737-700
2003
Boeing 737-800
1998
Bombardier Dash 8 Q400
2008
operated by LGW
Fokker 100
2004
2009

Fleet policy

The average age of the fleet is currently 5.9 years. Continuous investments in fuel-efficient aircraft mean that Air Berlin jets now use less fuel and produce lower emissions and noise levels. In 2010 Air Berlin reduced its average fuel consumption by 1.1 per cent to 3.60 litres per 100 passenger kilometres. In May 2001 Air Berlin became the first company in the world to take delivery of a Boeing 737-800 retrofitted with blended winglets to save fuel and protect the environment; almost all the aircraft in the Air Berlin fleet have now been fitted with this equipment.

In February 2011 Air Berlin took delivery of its first Boeing 737-800 featuring the new "Sky Interior" cabin design. All new Boeing Next Generation aircraft operated by Air Berlin will in future include this improved interior, with its newly-designed side wall and baggage compartments, large window niches and indirect LED lighting.[53]

Incidents and accidents

Air Berlin has not experienced accidents or major incidents since its foundation.

Awards

See also

References

  1. ^ a b Annual Report 2010. ir.airberlin.com. Retrieved on 2011-04-21.
  2. ^ airberlin Strategy and Business Model. Air Berlin, retrieved on 19 January 2011.
  3. ^ Berlin Tegel still Air Berlin’s #1 base
  4. ^ News. oneworld (2010-07-26). Retrieved on 2010-12-15.
  5. ^ "Approach map." Air Berlin. Retrieved on 5 May 2010.
  6. ^ Investor Relations Page on airberlin.com
  7. ^ Air Berlin reveals 2010 passenger numbers
  8. ^ Nicholson, Michael (May-June 2009). "Air Berlin: born out of a political situation". Airliners. 
  9. ^ Berlin Airport Company, Monthly Timetable Booklets for Berlin Tempelhof and Berlin Tegel Airports, Berlin Airport Company, West Berlin, various editions April 1968 – October 1990
  10. ^ Photos: Boeing 707–331 Aircraft Pictures. Airliners.net (2006-05-26). Retrieved on 2010-12-15.
  11. ^ a b Berlin Airport Company, April 1979 Monthly Timetable Booklet for Berlin Tempelhof and Berlin Tegel Airports, Berlin Airport Company, West Berlin, 1979
  12. ^ Berlin Airport Company, April 1980 Monthly Timetable Booklet for Berlin Tempelhof and Berlin Tegel Airports, Berlin Airport Company, West Berlin, 1980
  13. ^ Berlin Airport Company, April 1981 Monthly Timetable Booklet for Berlin Tempelhof and Berlin Tegel Airports, Berlin Airport Company, West Berlin, 1981
  14. ^ "World Airline Directory." Flight International. 30 March 1985. 34." Retrieved on 21 August 2009.
  15. ^ a b Berlin Airport Company, April 1989 Monthly Timetable Booklet for Berlin Tempelhof and Berlin Tegel Airports, Berlin Airport Company, West Berlin, 1989
  16. ^ a b c airberlin.com:History
  17. ^ "World Airline Directory 1979". Flight International. March 1979. 
  18. ^ Repricing of IPO
  19. ^ Air Berlin acquires dba, Air Berlin Press Release
  20. ^ air-berlin places 57 billion boeing order, news.blogs.inforefinery.com, 28 November 2006
  21. ^ Boeing: Boeing, Air Berlin announce order for 25 787 Dreamliners
  22. ^ David Kaminski-Morrow (3 April 2007). "Air Berlin LTU move driven by access to Düsseldorf". Flight International: p. 9. 
  23. ^ Air Berlin seeks to buy Condor, give T. Cook stake, Reuters, Frankfurt, 20 September 2007
  24. ^ Airways (Qubein, R., The Two Faces of Air Berlin), Vol. 17, No. 9, pp. 35, Airways International Inc., Sandpoint, November 2010
  25. ^ Air Berlin Magazine(German)
  26. ^ Vilaweb, 5 June 2008.(Catalan)
  27. ^ Vilaweb, 6 June 2008.(Catalan)
  28. ^ Business finance news – currency market news – online UK currency markets – financial news – Interactive Investor, Iii.co.uk, Retrieved on 15 december 2010.
  29. ^ Air Berlin enters into co-operation with Hainan Airlines
  30. ^ TUI Travel PLC and Air Berlin seal strategic alliance for their German flight business
  31. ^ Air Berlin information on the taking over of TUIfly routes. Retrieved 31 October 2009.
  32. ^ ESAS Holding A.S. acquires a 15 percent stake in Air Berlin PLC
  33. ^ Air Berlin announces cooperation with Pegasus Airlines. Retrieved 2010-01-24.
  34. ^ Air Berlin enters into cooperation with Bangkok Airways
  35. ^ Air Berlin is expanding its codeshare arrangements with S7 Airlines
  36. ^ Air Berlin PLC / Increase in shareholding in Niki from 24% to 49.9% is completed
  37. ^ "Air Berlin to join oneworld alliance". Seattle Post-Intelligencer. 26 July 2010. http://blog.seattlepi.com/aerospace/archives/215767.asp?source=rss. Retrieved 26 July 2010. 
  38. ^ Air Berlin to join oneworld alliance
  39. ^ Air Berlin concludes codeshare agreements with American Airlines and Finnair after joining oneworld
  40. ^ follow me entertainment: Joint take-off for airberlin and kick-media
  41. ^ airberlin, Germania, Harder & Partner and Berlin Airports celebrate laying of foundation stone for first maintenance hangar at BBI
  42. ^ airberlin: Successful LTU Integration
  43. ^ airberlin focuses increasingly on Düsseldorf
  44. ^ airberlin and British Airways: codeshare agreement from July
  45. ^ airberlin flightschool.
  46. ^ airberlin Shareholder structure. ir.airberlin.com, retrieved on 22 December 2011.
  47. ^ airberlin technik.
  48. ^ airberlin Service on board. Air Berlin, retrieved on 19 January 2011.
  49. ^ airberlin Business Class. Air Berlin, retrieved on 19 January 2011.
  50. ^ http://www.nasdaq.com/aspx/stock-market-news-story.aspx?storyid=201107080525dowjonesdjonline000281&title=air-berliniberia-start-code-share-agreement
  51. ^ Air Berlin fleet list at planespotters.net
  52. ^ Air Berlin historic fleet list at airfleets.net. Retrieved 2011-04-18.
  53. ^ First ever Boeing 737-700 with Sky Interior delivered to airberlin.
  54. ^ a b c d e Air Berlin awards
  55. ^ World Winners 2008, World Travel Awards
  56. ^ Business Travel Awards 2011 – Winners 2010. Businesstravelawards.com (2010-10-25). Retrieved on 2010-12-15.
Bibliography

External links