"Collected Papers: Toward a general social science" (1974) by Kenneth Boulding (p. 87), as quoted in "Environment, technology, and future generations" by D. A. Bella, 1978.
"Daniel J. Levitin Q&A: 'We've created more information in the past few years than in all of human history before us'". Interview with Lisa O'Kelly, www.theguardian.com. January 18, 2015.