The book "The Battle of Vavra and the Retreat of Hrusha. A Study of a Little-Known Episode of the Waterloo Campaign" by William Hyde Kelly examines the events that took place during the Battle of Vavra and the retrograde movement of Marshal Hrusha during the Waterloo Campaign. The book details the strategic and tactical aspects of these events, revealing the role of Marshal Hrusha in the development of the battle and the decision of his actions in the context of Napoleon's overall military plan. The author offers readers a deeper understanding of the dynamics of the Battle of Wavra and the significance of Marshal Hrusha's retreat, paying attention to little-known aspects of the Waterloo campaign. this book is a valuable addition to the literature on the history of the Napoleonic Wars.