Virgil, Aeneid 5.560-562
The Troy Game.
tres equitum numero turmae ternique vagantur
ductores; pueri bis seni quemque secuti
agmine partito fulgent paribusque magistris.
Three in number are the troops of horse, and three leaders range in front. Twice-six boys follow each leader; divided into ranks, each with a commander, they gleam.