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NK Brahma, Philosophy of Hindu Sādhanā, pages ix-x
C.C. Shah, Cultural and Religious Heritage of India: Jainism, Mittal, page 301
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Valmiki Ramayana - translated by RALPH T. H. GRIFFITH, M. A Table 3, Point 15 Nishkam Sadhana; Sanatan Sanstha; Sakam Sadhana; Sanatan Sanstha
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