Related Rule
Argentina
Practice Relating to Rule 70. Weapons of a Nature to Cause Superfluous Injury or Unnecessary Suffering
Argentina’s Law of War Manual (1969) states that “the use of weapons, projectiles or material which can cause unnecessary suffering” is especially prohibited. It adds: “The projectiles and weapons covered by this prohibition shall be determined solely by the common practice of States to refrain from using certain means of warfare in recognition that they cause such suffering.” 
Argentina, Leyes de Guerra, RC-46-1, Público, II Edición 1969, Ejército Argentino, Edición original aprobado por el Comandante en Jefe del Ejército, 9 May 1967, § 1.008(1).
Argentina’s Law of War Manual (1989) provides: “The use of weapons, projectiles, materials and methods of warfare of a nature to cause superfluous injury or unnecessary suffering is prohibited.” 
Argentina, Leyes de Guerra, PC-08-01, Público, Edición 1989, Estado Mayor Conjunto de las Fuerzas Armadas, aprobado por Resolución No. 489/89 del Ministerio de Defensa, 23 April 1990, § 1.04(2).
In the Military Junta case in 1985, Argentina’s National Court of Appeals, with reference to Articles 22 and 23 of the 1907 Hague Regulations, mentioned the prohibition on the use of weapons, projectiles or material which cause “unnecessary damage” to enemies. It also referred to the opinion of some writers, according to whom unnecessary harm to the enemy or to the civilian population is prohibited. 
Argentina, National Court of Appeals, Military Junta case, Judgment, 9 December 1985.