A brief treatise translated into English written by Imam Muhammad ibn Abdulwahhab (may Allah have mercy on him) in which he talks about the prayer, the greatest pillar of Islam after monotheism. He mentions its conditions, duties, and pillars.
A book translated into English in which Imam Ibn Taymeyya shows the contradictions that the Christians have. This book is one of the most important Islamic books which gives right answers about Christianity.