Fr. Dubay is most known for his work Fire Within, which is a classic of spirituality and which I would recommend to anyone who is serious about deepening their life of prayer. However, it is not even my favorite Dubay book. That would be Happy Are You Poor, in which Fr. Dubay argues (persuasively, in my mind) that every Christian should live a life of poverty. And if you think you know what he means by that, I challenge you to read the book to actually find out.
May the souls of the faithful departed, through the mercy of God, rest in peace.