Related Rule
Germany
Practice Relating to Rule 19. Control during the Execution of Attacks
Germany’s Military Manual (1992) provides: “An attack shall be suspended if it becomes apparent that the objective is not a military one or is subject to special protection or that the attack may be expected to cause excessive incidental loss of civilian life or damage.” 
Germany, Humanitarian Law in Armed Conflicts – Manual, DSK VV207320067, edited by The Federal Ministry of Defence of the Federal Republic of Germany, VR II 3, August 1992, English translation of ZDv 15/2, Humanitäres Völkerrecht in bewaffneten KonfliktenHandbuch, August 1992, § 457.