To inform, and, therefore to reconnoitre, this is the first and constant duty of the advanced guard. Ferdinand Foch
When we say "the state," the state is We, it is we, it is the proletariat, it is the advanced guard of the working class. Vladimir Lenin
Caesar overtook his advanced guard at the river Rubicon, which formed the frontier between Gaul and Italy. Well aware how critical a decision confronted him, he turned to his staff, remarking: "We may still draw back but, once across that little bridge, we shall have to fight it out." Suetonius