Ustad Bade Ghulam Ali Khan- Origins of Ragas

Even though this discussion is already available on KZbin, I decided to upload it here due to a fascinating topic of the origins of Raags in Bharatiya Artistic Music.
You may find the following important relevant articles/books interesting to read:
1) राग (Marathi book 2005/2015) by Kiran Phatak
2) भारतीय संगीत - एक आढावा (1962) an article included in the book entitled मागोवा by Narhar Kurundkar
www.narharkurundkar.com/index...
3) संगीत दर्पण (Sanksrit Text) by Damodar Pandit and त्यावरील प्राचीन मराठी गद्य टीका (1985) by Shridhar Kulkarni
4) दत्तिलम् (Sanskrit Text)
5) बृहद्देशी (Sanskrit Text) by Sri Matanga Muni
6) संगीत रत्नाकर (Sanskrit Text)
7) मकाम, दस्तगाह, आणि राग : this Marathi article is included in the book titled संगीतविचार by Professor Ashok Da Ranade
8) भारतीय संगीत का इतिहास by Dr. Thakur Jaydev Singh
9) The Ragas of Early Indian Music: Modes, Melodies and Musical Notations from the Gupta Period to c. 1250 (1995) by Richard Widdess (Oxford University Press)
10) Evolution of Raga and Tala in Indian Music (1989) by M. R. Gautam
11) Ragas and Raginis (1935/2004) by O. C. Gangoly
12) The Origin of Raga (1981/2015) by S. Bandopadhyaya
13) The Raga-ness of Ragas (2016) by Deepak Raja
14) Nad Understanding Raga Music (1998) by Sandeep Bagchee