Shiva Purana
भृशं चैव प्रवक्ष्यामि युद्धधर्मं सनातनम् ॥ यादृशाय प्रहर्तव्यं यादृशं परिवर्जयेत्॥ ३४॥
Now I shall explain clearly the eternal virtue concerning war, as to who can be attacked and hit and who shall be spared.
english translation
bhRzaM caiva pravakSyAmi yuddhadharmaM sanAtanam ॥ yAdRzAya prahartavyaM yAdRzaM parivarjayet॥ 34॥
hk transliteration by Sanscript