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2. Visnu Purana, Amsa 1, Canto 19, Verse 41.
3. Beecher, H. W.; Proverbs from Plymouth Pulpit (1887).
4. Einstein, Albert; Out of My Later Years
5. Mukherjee Haridas and Uma Mukherjee; A Phase of Swadeshi Movement. National Education: (1953).
6. 6. Manoj Das; Sri Aurobindo in the First Decade of the Century (1972).