Соответствующая норма
Practice Relating to Rule 21. Target Selection
Kenya’s LOAC Manual (1997) states:
When a choice is possible between several military objectives for attaining a similar military advantage, the objective to be selected shall be that objective, the attack on which would cause the least danger to civilian persons and objects. 
Kenya, Law of Armed Conflict, Military Basic Course (ORS), 4 Précis, The School of Military Police, 1997, Précis No. 4, p. 8.