Masao Abe 
Buddhism and Interfaith Dialogue [PDF ebook] 
Part one of a two-volume sequel to Zen and Western Thought

This book tries to clarify a Buddhist view of interfaith dialogue from various points of view. It discusses how the Buddhist notion of Sunyata (Emptiness) works dynamically for mutual understanding and transformation of world religions. It also analyzes dialogue between Buddhism and Contemporary Christian theology, especially that of Paul Tillioh and Langdon Gillay.