Related Rule
Switzerland
Practice Relating to Rule 115. Disposal of the Dead
Section D. Burial in individual or collective graves
Switzerland’s Basic Military Manual (1987) states: “If possible, corpses shall be buried separately.” 
Switzerland, Lois et coutumes de la guerre (Extrait et commentaire), Règlement 51.7/II f, Armée Suisse, 1987, Article 76, commentary.