hi, here is the references you will need in my paper.
1.Explainingthefuture.com. (2014). 3D printing (the new industrial revolution). Retrieved from http://www.explainingthefuture.com/3dp_book.html
2.Hall, R. (1986). The relation between price and marginal cost in US industry. Retrieved from: http://www.nber.org/papers/w1785.pdf
3.Madden, S. (2013).United States Securities and Exchange Commission
Washington, DC 2054. Annual Report
4.Yan, B. and Roberts, M. (1985). Measuring Quality Change in Quota-constrained import markets. The Case of U.S. Footwear. Journal of International Economics 21 (1986) 45-60. North-Holland
5.Zeeshan, H. (2014).Stepping down: Import penetration will stifle demand, forcing operators to change strategies. IBISWorld Industry Report
6.Zeeshan, H. (2014). Stepping down: Low-cost imports and a poor economic outlook will hurt the industry. IBISWorld Industry Report