Translations for formal in French

Here are paragraphs from public domain books translated:

The doctor, whose hand was trembling a little, seized his revolver. Nevertheless, he did not move, remembering the formal orders which he had received and fearing to act against them.	Le docteur, dont la main tremblait un peu, saisit son revolver. Il ne bougea pas néanmoins, se rappelant l’ordre formel qui lui avait été donné, et redoutant de prendre une décision contraire.
The Confessions of Arsene Lupin, by Maurice Leblanc	Les Confidences d’Arsène Lupin, de Maurice Leblanc