With diacritics: Thích Nhất Hạnh

From his website:

Zen Master Thich Nhat Hanh is a global spiritual leader, poet and peace activist, revered around the world for his pioneering teachings on mindfulness, global ethics and peace.

and Wikipedia:

Nhất Hạnh has published over 130 books, including more than 100 in English which have sold over 5 million worldwide. He is active in the peace movement and deep ecology, promoting nonviolent solutions to conflict and raising awareness of the interconnectedness of all elements in nature. He is the founder of the largest monastic order in the West.