André Geraque Kiffer 
Battle Of The Indus River, November 24, 1221 [PDF ebook] 

In the simulation of the Battle of the Indus River we will test the Persian Mamluk army by adopting a concave battle order, which has its best use in the situation where a defense initially yields, intentionally or unintentionally, its center. The Persian Mamluk phasing of the battle will begin by advancing the center against the Mongol line; and will evolve into the retreat of this block between the wings, maintaining position at the bottom of the concavity, when then the wings will press against the flanks of the Mongols, trying to channel them.