Related Rule
Argentina
Practice Relating to Rule 28. Medical Units
Argentina’s Law of War Manual (1969) restates Article 27 of the 1907 Hague Regulations, Articles 19 and 21–22 of the 1949 Geneva Convention I and Articles 18–19 of the 1949 Geneva Convention IV. 
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, §§ 1.010, 3.007 and 4.004(1) and (2).
Argentina’s Law of War Manual (1989) states: “Civilian and military medical units shall be respected and protected in all circumstances and may not be made the object of attack.” 
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, § 2.11; see also § 2.03.
This rule is repeated with respect to non-international armed conflicts. 
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, § 7.07.
The manual further states:
The protection of medical units ceases only when they are used to commit acts hostile to the enemy, for example, the accommodation of healthy soldiers and the installation of observation posts, etc. The protection ceases only after a warning, setting a reasonable time-limit, has remained unheeded. 
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, § 2.12.
Argentina’s Code of Military Justice (1951), as amended in 1984, punishes “whoever attacks, without any necessity, hospitals … which are marked by the appropriate distinctive signs”. 
Argentina, Code of Military Justice, 1951, as amended in 1984, Article 746(2).
In 1993, during a debate in the UN Security Council on the situation in the former Yugoslavia, Argentina stated that “the deliberate attacks on … hospitals” could not go on with impunity. 
Argentina, Statement before the UN Security Council, UN Doc. S/PV.3203, 20 April 1993, p. 57.