Mountain warfare

Mountain warfare refers to warfare in the mountains or similarly rough terrain. This type of warfare is also called Alpine warfare, after the Alps mountains. Mountain warfare is one of the most dangerous types of combat as it involves surviving not only combat with the enemy but also the extreme weather and dangerous terrain.

Mountain ranges are of strategic importance since they often act as a natural border, and may also be the origin of a water source (e.g. Golan Heights – water conflict). Attacking a prepared enemy position in mountain terrain requires a greater ratio of attacking soldiers to defending soldiers than a war conducted on level ground. Mountains at any time of year are dangerous – lightning, strong gusts of wind, rock falls, avalanche, snow pack, ice, extreme cold, glaciers with their crevasses and the general uneven terrain and the slow pace of troop and materiel movement are all additional threats to combatants. Movement, reinforcements, and medical evacuation up and down steep slopes and areas where even pack animals cannot reach involves an enormous exertion of energy.

History

Early history

The term mountain warfare is said to have come about in the Middle Ages after the monarchies of Europe found it difficult to fight the Swiss armies in the Alps. This was because the Swiss were able to fight in smaller units and took vantage points against a huge unmaneuverable army. Similar styles of attack and defence were later employed by guerrillas, partisans and irregulars who hid in the mountains after an attack, making it challenging for an army of regulars to fight back. In Bonaparte's Italian campaign, and the 1809 rebellion in Tyrol, mountain warfare played a large role.

World War I

Italian Front in 1915-1917: eleven Battles of the Isonzo and Asiago offensive. In blue, initial Italian conquests.

Mountain warfare came to the fore once again, during World War I, when some of the nations involved in the war had mountain divisions that had hitherto not been tested. The Austro-Hungarian defence repelled the Italians as they took advantage of the mostly mountainous terrain in the Julian Alps and the Dolomites, where more people succumbed to frostbite and avalanches than to bullets. During the summer of 1918, the Battle of San Matteo took place on the Italian front, this battle was fought at the highest elevation of any in the war. In December 1914, another offensive was launched by the Turkish supreme commander Enver Pasha with 95,000-190,000 troops against the Russians in the Caucasus. Insisting on a frontal attack against Russian positions in the mountains in the heart of winter, the end result was devastating and Enver lost 86% of his forces.

World War II

• Battles of Narvik
• Kokoda Track campaign
• Operation Renntier
• Operation Gauntlet

Kashmir conflicts

Further information: Kashmir conflict

The most dangerous and volatile of all mountain conflicts involves the ongoing one between India and Pakistan over the Kashmir region. Since the partition in 1947, both countries have been constantly locked in skirmishes and wars mainly in this Himalayan region with the highest mountains in the world. The first hostilities between the two nations in the Indo-Pakistani War of 1947 showed that both were ill-equipped to fight in biting cold, let alone at the highest altitudes in the world.

During the Sino-Indian War of 1962, hostilities broke out between the Republic of India and the People's Republic of China at some of the highest altitudes over the Himalayan mountains.

Later wars between India and Pakistan were mainly fought in the valleys rather than in the mountains, although several major mountain battles took place in all these conflicts. This changed in the Kargil War when Indian forces were faced with the huge task of flushing out intruders and disguised Pakistani soldiers who had captured high mountain posts. This proxy warfare became the only modern war that was fought exclusively on mountains. As a result of its experiences in mountain warfare in Kargil, the Indian Army now conducts courses on specialized artillery use in the mountains, where ballistic projectiles have different characteristics.

Falklands War

Landscape of South Georgia

Although most of the Falklands War took place in the Falkland Islands themselves, on hilltops in semi-Arctic conditions, during the earlier stages of the war, there was some action in the bleak mountainous island of South Georgia. South Georgia is a periantarctic island, and since the war took place during the southern winter, Alpine conditions prevailed almost down to sea level. It was unusual, in that it combined aspects of deep water long range expeditions, Arctic warfare and mountain warfare.

Operation Paraquet was ordered by British Admiral Fieldhouse on 12 April 1982. It was to involve Mountain Troops from D Squadron SAS in Ascension, 150 Royal Marines on the tanker Tidespring, 2SBS on Plymouth and 6SBS in the submarine Conqueror. Conqueror was first on the scene and carried out a survey of key areas of the South Georgia coast. The operation was originally supposed to involve both SAS and SBS forces being infiltrated onto South Georgia by helicopters from the Tidespring and Antrim, but the plan had to be changed when the two Wessex helicopters transporting the SAS troops to an ambitious location on the west coast crashed in atrocious weather conditions on Fortuna Glacier; the troops and aircrew were rescued by Antrim's Wessex helicopter, the last remaining to the expedition.

Topography

War in Afghanistan

Australians patrolling isolated communities in the mountains of Oruzgan Province

Throughout history but especially since 1979, many mountain warfare operations have taken place throughout Afghanistan. Since the coalition invasion of Afghanistan in 2001 these have been primarily in the eastern provinces of Kunar and Nuristan.

Kunar and eastern Nuristan are strategic terrain. The area constitutes a major infiltration route into Afghanistan, and insurgents can enter these provinces from any number of places along the Pakistani border to gain access to a vast network of river valleys. In this part of Afghanistan (Regional Command East) the US military has adopted a hybrid style of mountain warfare incorporating counterinsurgency (COIN) theory where the population is paramount as the center of gravity in the fight. In COIN, seizing and holding territory is less important than avoiding civilian casualties. The primary goal of COIN is to secure the backing of the populace and thereby legitimize the government rather than focus on militarily defeating the insurgents. While this theory was successfully implemented in Iraq, it has been difficult to implement in Kunar and Nuristan. In the sparsely populated mountain regions of Eastern Afghanistan, strategists have argued for holding the high ground—a tenet of classical mountain warfare. The argument suggests that if the counterinsurgent does not deny the enemy the high ground, then the guerillas will be able to attack at will. In the Kunar and Nuristan regions US forces continue to pursue a hybrid style of COIN warfare, with its focus on hearts and minds, and mountain warfare, whereby the US forces seize and hold the high ground.

Mountain warfare training

The expense of training mountain troops precludes them from being on the order of battle of most armies except those who reasonably expect to fight in such terrain. Mountain warfare training is arduous and in many countries is the exclusive preserve of elite units such as special forces or commandos, who as part of their remit should have the ability to fight in difficult terrain (e.g. the Royal Marines). Regular units may also occasionally undertake training of this nature.

Austria and Germany

Gebirgsjäger of the German Army during a climbing exercise

Gebirgsjäger is the German word for mountain infantry (Gebirge meaning "mountain range", and Jäger meaning "hunter" or "ranger"). The word Jäger is the traditional German term for light infantry.

The mountain infantry of Austria have their roots in the three "Landesschützen" regiments of the Austro-Hungarian Empire. The mountain infantry of Germany carry on certain traditions of the Alpenkorps (Alpine corps) of World War I. Both countries' mountain infantry share the Edelweiss insignia. It was established in 1907 as a symbol of the Austro-Hungarian Landesschützen regiments by Emperor Franz Joseph I. These troops wore their Edelweiss on the collar of their uniforms. When the Alpenkorps came to aid the Landesschützen in defending the Austro-Hungary's southern frontier against the Italian attack in May 1915, the grateful Landesschützen honoured the men of the Alpenkorps by awarding them their own insignia: the Edelweiss.

Today the traditions of the Austrian mountain infantry (Gebirgsjäger) are maintained by the 6th Jägerbrigade in Innsbruck, subdivided in three battalions (Jägerbataillon 23, Jägerbataillon 24 and Jägerbataillon 26).

Honouring tradition, upon the creation of the Bundeswehr in 1955, the mountain infantry returned as a distinctive arm of the German army. Until 2001, they were organized as the 1. Gebirgsdivision, but this division was disbanded in a general reform. The successor unit is Gebirgsjägerbrigade 23 which has its headquarters in Bad Reichenhall (Bavaria). Battalions of these mountain infantry are deployed in southern Bavaria.

The soldiers of the mountain infantry wear a grey cap (“Bergmütze”) with an Edelweiss on its left side. This distinguishes them from all other German army soldiers who wear berets. The formal uniform, which is based on traditional skiing outfits, is also different from the standard German military uniform, and consists of ski jacket, stretch trousers and ski boots.

The “Kaiserjägermarsch” (March of the Kaiserjäger) from 1914 is the traditional military march of the German and Austrian mountain infantry.

Bulgaria

Bulgaria's 101st Alpine Battalion (101-ви алпийски батальон), based in Smolyan, is currently the only Bulgarian unit specialized in mountain warfare. A unique feature is their armament - Mosin–Nagant rifles, which were selected due to their excellent performance in high-altitude warfare. The battalion also has portable 60-mm mortars.

The unit is experienced in the terrain of the Rhodope Mountains, and during the Cold War it has extensively trained for operations against Greek and Turkish forces.

France

Chasseurs alpins at training

Until 1859, Italy wasn't yet a unified state but a sum of kingdoms and independent republics (Kingdom of Naples, Republic of Venice, Papal States, etc.). The situation changed with the unification of Italy. France saw this geopolitical change as a possible threat from the other side of the Alps border, partially as the Italians were the first to raise a corps of mountain warfare troops - the Alpini.

The French solution was to create its own mountain corps in order to oppose a possible Italian invasion through the Alps. By December 24, 1888, a law created a troupes de montagne ("mountain troops") corps. 12 of the 31 existing Chasseurs à Pied ("Hunters on Foot") battalions were selected to be converted. These first units were named Bataillons Alpins de Chasseurs à Pied ("Hunters on Foot Alpine Battalions"), later shortened to Bataillons de Chasseurs Alpins ("Alpine Hunters Battalions").

Since 1999 they have been (with other units) part of the 27th Mountain Infantry Brigade (Brigade d'Infanterie de Montagne), and are currently organised into three battalions:

• 7th Battalion, Bourg-Saint-Maurice
• 13th Battalion, Chambéry
• 27th Battalion, Cran-Gevrier (Annecy)

All three battalions are based in cities in the French Alps, thus the name of the units.

The Chasseurs are easily recognised by their wide beret (when not in battle uniform), named tarte (= pie). The British Army adopted the beret in the 1920s after having seen similar berets worn by the 70th Chasseurs Alpins (now disbanded).

Other mountain troops in the French armed forces comprise artillery (currently the 93rd Mountain Artillery Regiment - 93ème RAM) light armoured cavalry (4ème Régiment de Chasseurs), the 2nd Foreign Engineer Regiment (2ème REG) and the 2nd Company of the 2nd Foreign Parachute Regiment . The Gendarmerie Nationale has her own mountain units: PGM (Peloton de Gendarmerie de Montagne) and PGHM (Peloton de Gendarmerie de Haute Montagne) devoted to mountain rescue and law enforcement.

India

The Indian Army is among the most experienced and best trained in mountain warfare having fought numerous conflicts in the Himalayas in Arunachal Pradesh and Jammu and Kashmir while maintaining one of the largest active contingents of mountain warfare forces in the world, giving the Indian Army some of the most extensive and well-developed Mountain Warfare capabilities. Major conflicts include the 1962 Sino-Indian War and the Kargil War in 1999. Siachen Glacier is the world's highest battlefield, with about 3000 Indian troops on year round deployment on the edge of a glacier. For over two decades, India & Pakistan have fought numerous skirmishes in this most inhospitable of mountain territories, at altitudes over 6000 meters (20,000 feet) and at temperatures as low as -50 Celsius.

Due to the instability in the region and the need for permanent deployments in the mountainous regions, India's mountain warfare units were vastly expanded after the 1962 war, with the creation of 6 Mountain Divisions. The Indian Army presently has 10 Army Divisions dedicated to mountain warfare (8 Mountain Divisions and 2 Mountain Strike divisions) and another infantry division earmarked for high altitude operations. Each division has a personnel strength of 10,000-13,000 troops and consists of 3 brigades with 3,000 to 4,500 men each, including support elements such as signals, provost, and intelligence units.

In 2008, the Indian Army has sanctioned plans to raise two additional mountain divisions, with goals to be operational in five years. The two divisions will also have extensive air assets, including Utility helicopters, Helicopter gunships and Attack helicopters.

Training:
The Indian Military Academy (IMA), Dehradun conducts preliminary mountaineering and mountain warfare training for all Officer Cadets. Discontinued in the late 1980s, the Bhadraj Camp was revived in 1999 after the Kargil War. The culmination is a course of a 40 km run and climbing a 5500 feet cliff with a fully loaded pack at night.

For more specialized training, the Army operates the Parvat Ghatak School (Hindi: पर्वत घातक, Mountain Strike or Mountain Warrior) at Tawang, Arunachal Pradesh. This high-altitude commando school is the highest of its kind at 15,000 feet. With the mercury dipping to minus 20 degrees providing a freezing tougher terrain to impart training in conditions similar to Siachen.

Another school, the High Altitude Warfare School (HAWS) is located near Gulmarg, Jammu and Kashmir. Set up in 1948 as the 19 Infantry Division Ski School, HAWS has over the years become the Indian Army's nodal center for "specialised training and dissemination of doctrines" in high-altitude, mountain and snow warfare. HAWS Mountain warfare courses are conducted in the Sonamarg area, and snow-craft & winter warfare training in the Gulmarg area. HAWS played an important role during the Kargil War by conducting crash courses for troops prior to their deployment.

Given the extensive experience of the Indian Army in mountain warfare, troops from other nations regularly train and conduct joint exercises at these schools. Because of its experience in fighting wars in mountain regions for over 50 years, as well as its history of recruitment of natives from the Himalayan regions of India and Nepal (such as Gurkha, Kumaon, Garhwal and Dogras), Indian Mountain Warfare Units are considered among the best in the world. Numerous army units across the world are now implementing training modules modeled after Indian Mountain Warfare training systems. These include forces from UK, US, Russia, Israel, etc. In 2004, US special forces teams were sent to India to learn from Indian Army experiences of the Kargil War prior to their deployment for operations in Afghanistan. Russian troops also trained at the High Altitude Warfare School in Gulmarg for operations in Chechnya. They also visited Siachen and other Army posts.

Israel

The Alpinist Unit is the Israeli mountain unit. Unlike most of the Israeli Forces, they are not trained by the ages 18–19, but after their standard serving time (by their request), no earlier than 22-23.

Italy

Italian Alpini from the 7th Alpini Regiment during an exercise

The Alpini are the elite mountain warfare infantry of the Italian Army. They are currently organised in the Julia and Taurinense alpine brigades, which are subordinated to the Alpine Troops Command. The singular is "Alpino".

Formed in 1872, their mission was to protect Italy's northern mountainous borders. On June 7, 1883, the Alpini were awarded the "fiamme verdi" (green flames) collar patch, thus elevating them to an speciality within the Italian Infantry Corps. Also adopted was their distinctive headdress; the "Cappello Alpino" with its black feather, which led to them being nicknamed "Le Penne Nere" or "the black feathers".

They distinguished themselves during World War I as they fought against Austro-Hungarian soldiers in what has since been called the "War in snow and ice". During World War II, the Alpini fought mostly on the Eastern Front being tasked to hold the front in the Don river plains.

In the 1990s, after the end of the Cold War, three of the five Alpini brigades and many support units were disbanded due to the reorganization process of the Italian Army. Currently, despite having some of the best trained and best equipped mountain troops in the world, the military role of Alpines is seen in terms of peacekeeping missions and minor disputes interventions.

The 4th Alpini Parachutist Regiment is a Special Operations Force unit specialized in the airborne assault role and comparable to the United States Army Rangers. It originated from the Alpini Paratrooper platoons in each of the five Alpini Brigades, which were merged on 1 April 1964 in the Alpine Paratroopers Company.

The "Centro Addestramento Alpino" Aosta is the Armys school responsible for the mountain training of its troops. The 6th Regiment is based in Innichen in the province of South Tyrol and directly subordinated to the Alpine Troops Command (COMALP). It functions as a NATO-wide high altitude warfare training centre and administers the Training Areas in the Puster Valley.

Romania

Romanian Vânători de Munte.

The Vânători de Munte ("Mountain Hunters/Rangers", Romanian pronunciation: [vɨnəˈtorʲ de ˈmunte]) are the elite mountain troops of the Romanian Land Forces. They were first established as an independent Army Corps in 1916 during World War I, and became operational in 1917 under Corpul de Munte designation.

Thought as of being elite troops, the Romanian Vânători de Munte saw action in World War II on the Eastern Front in some of the harshest battles - including the battles of Sevastopol and Stalingrad - where their performance lived up to their reputation: virtually all their commanders from brigade level and up received the Knight's Cross of the Iron Cross.

There are currently two brigades operational, one subordinated to the 1st Territorial Army Corps (the 2nd Mountain Troops Brigade), and another one subordinated to the 4th Territorial Army Corps (61st Mountain Troops Brigade). Mountain troops are participating in peacekeeping missions in Afghanistan.

Pakistan

In the Pakistan Army, mountain training is considered part of overall training and all soldiers and units are expected to be proficient at it. Almost all units of all arms serve tours in Kashmir and Northern Areas, often in active duties on the LOC or Siachin. The Pakistan Army’s High-Altitude School, at Rattu in Northern Kashmir, is an ideal location on the confluence of the Hindukush, Himalayas, and Karakorum ranges. The school conducts training throughout the year and includes mountain climbing on peaks ranging from 15,000 to 20,000 feet and survival on glaciated terrain and in snowy and icy conditions.

Poland

Soldiers of the 21st Podhale Rifles Brigade in full gala dress-suit, Warsaw, 2006

Podhale rifles (Polish: Strzelcy podhalańscy) is a traditional name of the mountain infantry units of the Polish Army. Formed in 1918 out of volunteers of the region of Podhale, in 1919 the smaller detachments of Podhale rifles were pressed into two mountain infantry divisions, the 21st Mountain Infantry and 22nd Mountain Infantry Divisions, as well as into three brigades of mountain infantry. The units were roughly equivalent to the German Gebirgsjäger troops. Currently Polish Army maintains one brigade of mountain infantry.

Spain

Spain has a Brigade of Mountains troop:

• Brigada de Cazadores de Montaña "Aragón" I (1st Mountain Brigade)
• Regimiento de Cazadores de Montaña "Galicia" 64 (64th Mountain Regiment)
• Regimiento de Cazadores de Montaña "America" 66 (66th Mountain Regiment)
• Grupo de Artillería de Montaña I (1st Mountain Artillery Battalion)
• Grupo Logístico de Montaña I (1st Mountain Logistic Battalion)
• Batallón de Cuartel General I (1st Headquarters Battalion)
• Unidad de Zapadores de Montaña 1 (1st Mountain Sapper Company)

Sweden

Mountains constitute almost half the area of Sweden, including its northern border. Winter and mountain warfare skills were therefore always important to the country. Between 1945 and 2000 Sweden trained and deployed several companies per year at the Army Ranger School and later the Lapland/Arctic Mountain Ranger regiment (I22) in Kiruna (located some 150 kilometres north of the arctic circle in Lapland). The school/regiment drew on experiences gained during World War II from guarding and patrolling the mountainous northern borders and uninhabited inland mountain regions, as well as from light infantry and ski fighting in Finland in the wars against the Soviet Union. Later the army as a whole benefited from the Army Ranger School, as commanding and training officers as well as complete fighting units undertook training there. Exchanges were also organised with similar units in, for example, Finland, Norway, Germany, Austria, Switzerland, France, the UK, and the USA.

As part of major armed forces reductions in 2000 the Lapland ranger regiment (I22) in Kiruna was disbanded, and its several trained and equipped battalion and company sized field units were deactivated. More recently the army has created a dedicated mountain platoon. This is now based at the ranger detachment (known as Arméns Jägarbataljon or simply AJB) in Arvidsjaur (located 100 kilometres south of the arctic circle), since AJB is a detachment, it is a part of I19, Norrbottens regemente in Boden. The task for this single battalion is to guide other smaller units in the mountains besides taking on reconnaissance and fighting tasks.

Turkey

The Turkish Army has a mountain warfare specialized brigade (Bolu Commando Brigade) located at the city of Bolu in northwestern Turkey, which actually operates at the province of Hakkari and northern Iraq. The Hakkari Mountain Commando Brigade mostly performs counter-terrorism operations in this extremely rugged region of south-eastern Turkey, with an average elevation of 3500 meters and winter time temperatures below -30 degrees Celsius. The officers and soldiers of this brigade as well as other troops are trained in Egirdir Mountain and Commando School in Egirdir, near the city of Isparta. The training and facilities offered by the school are utilized by other members of NATO, and non-NATO countries such as Pakistan, Azerbaijan and some Eastern European countries.

Hakkari Mountain Commando Brigade has been at the forefront of counter-terrorism operations against PKK militant organization since late 1980s, and has participated in several cross-border operations and incursions into Iraq in hot pursuit of PKK militants. Most recently, in February 2008, the brigade has participated in the Operation Sun, in which 10,000 troops Turkish Armed Forces has entered and temporarily seized Iraqi territory utilized by PKK. The entire operation took part in the region of northern Iraq near Qandil Mountains in extreme winter conditions.

United Kingdom

In the United Kingdom the Royal Marines are the principal regular unit trained in mountain and cold weather warfare and have a specialised instructor cadre: the Mountain Leader Training Cadre. The capability is fielded by 3 Commando Brigade. The British Army also have the Mountain Troops of Special Air Service squadrons. During the Cold War the Royal Marines were assigned to the NATO Northern Flank, their task was to be part of the force defending the mountainous Nordic region from the Soviet Union.

United States

Main article: 10th Mountain Division (United States)

A map of the ANACONDA area of operations.

The US has a history in mountain warfare, the 10th Mountain Division served in the Italian Apennine Mountains in World War II. The Army National Guard has the Mountain 86th Infantry Brigade Combat Team consisting of battalions around New England. In the United States there are four training facilities dedicated to preparing for mountain and cold weather warfare: the Special Forces Advanced Mountain Operations School (SFAMOS) located in Ft Carson, Colorado, Army Mountain Warfare School located in Jericho, Vermont, the Northern Warfare Training Center located in Black Rapids, Alaska and the Marine Corps Mountain Warfare Training Center located in Pickel Meadows, California. These facilities offer challenging training in the most austere of training environments. American experience in mountain warfare continues to the present: see Operation Anaconda.

Brazil

The 11th Mountain Infantry Battalion served beside the US 10th Mountain Division in the Italian Apennine Mountains in World War II. Located in São João del Rei city this battalion develop the mountaineering techniques for the Brazilian Army. There are formed the Brazilian Mountain Guides. The 11th battalion has troops deployed in Haiti integrating the MINUSTAH.

Other countries

Swiss soldier abseiling in the Alps (2014)

At present the following armies have specialised alpine units or Mountain troops:

• Argentina: Cazadores de Montaña, 8th Mountain Infantry Brigade, 6th Mountain Infantry Brigade
• Chile: 3th Mountain Division (Tercera División de Montaña)
• Greece: Evzones Regiments (historical), Mountain Raiding Companies (modern)
• Netherlands: Mountain Leader Reconnaissance Platoon, Netherlands Marine Corps, And with in the Korps Commandotroepen, there are dedicated groups specialized in mountain warfare.
• Slovenia: 132nd Mountain Battalion, Multinational Centre of Excellence for Mountain Warfare
• Switzerland: there are currently two active and one reserve mountain infantry brigades in the Swiss Army: Brigata fanteria montagna 9, Brigade d'infanterie de montagne 10 (reserve), and Gebirgsinfanteriebrigade 12.

Besides those mentioned above: Armenia, China, Georgia (Sachkhere Mountain Training School), Russia, Turkey and Ukraine are also among the nations that field units specialized in mountain warfare.

References

• Frederick Engels, (January 27, 1857) "Mountain Warfare in the Past and Present" New York Daily Tribune MECW Volume 15, p 164

Further reading

• Govan, Thomas P. (1946-09-01). Training for mountain and winter warfare. AGF Study, no. 23. [Washington, D.C.]: Historical Section, Army Ground Forces. Retrieved 2011-01-28.
• Malik, Muhammad Asim (2004-09-10). "Mountain warfare: the need for specialized training" (PDF). Military Review. 84 (5): 94–102. ISSN 0026-4148. OCLC 2558412. Retrieved 2011-01-28.
• Pierce, Scott W. (2008-05-22). Mountain and cold weather warfighting: critical capability for the 21st century. SAMS Monograph. Fort Leavenworth, Kans.: School of Advanced Military Studies, United States Army Command and General Staff College. Retrieved 2011-01-28.

External links

• Official page of documentary film GLOBAL WARNING on the Mountain War 1915-1918 Global Warning
• Mountain War in World War I The war in the Italian Dolomites (Italian)
• Historic films showing Mountain Warfare in World War I at europeanfilmgateway.eu
• Mountain Combat World War II Militaria: Combat Lessons
• High Altitude Warfare School Of the Indian Army [1]
• Official Italian Army website page on Alpine Troops Command [2]
• Official page of 11th Mountain Infantry Battalion (Brazil) [3]