Nyanaponika Thera (2005). “The Heart of Buddhist Meditation: Satipaṭṭhāna : a Handbook of Mental Training Based on the Buddha's Way of Mindfulness, with an Anthology of Relevant Texts Translated from the Pali and Sanskrit”, p.25, Buddhist Publication Society
Speech at the Bombay Rotary Club on November 02, 1943. "Keynote: Excerpts from his speeches and chairman's statements to shareholders". Book by J. R. D Tata, 1986.