1. Singhi, N.Ludhiana India’s most polluted.Times of India, September 28, 2011.
2. Chauhan, C.CNG not that green: Pollution board.Hindustan Times, January 5, 2011.
3. Najar, N.India aims $1 billion at sacred but filthy Ganges.The New York Times, June 14, 2011.