1. 19. “Towards the Circular Economy” (Ellen MacArthur Foundation, Cowes, UK, 2012), vol. 1, available at http://www.ellenmacarthurfoundation.org/business/reports (accessed June 2015).
2. 57. National Institute of Environmental Health Services, “Bisphenol A (BPA),” available at http://www.niehs.nih.gov/health/topics/agents/sya-bpa (accessed March 2015).
3. The carbon footprint of reinforced concrete
4. The story of Bioglass®