To improve your endgame play it is essential to learn how to calculate the size of your territory and the value of your move. Regardless your playing style in the endgame it is counting that counts.
Rational endgames offers a clear explanation of modern Endgame theory. Problems are added to practice the theory.
Weaker players will observe that if they apply the rules given in this book in opening and middle game they will most certainly get better results. Stronger players will get a better understanding of their excisting endgame skills so hat they can aplly them more efficiently.