Related Rule
Argentina
Practice Relating to Rule 57. Ruses of War
Argentina’s Law of War Manual (1969) provides: “Stratagems or ruses of war and the employment of methods necessary for obtaining information about the enemy and the country are considered as lawful.” 
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, § 1.016.
The manual also states:
The observation of the principle of good faith must be constant and inalterable in dealings with the enemy. Consequently, the use of ruses and stratagems of war shall be legitimate as long as they do not imply the recourse to treachery or perfidy. 
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, § 1.017.
Argentina’s Law of War Manual (1989) states that stratagems are “acts which are intended to mislead an adversary or to induce him to act recklessly but which infringe no rule of international law and which are not perfidious”. It gives examples of stratagems, such as camouflage, mock operations and false information. 
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, § 1.05(3).