1. Al-moneef, M., 2006. The Contribution of the Oil sector to Arab Economic Development. OFID Pamphlet series Number 34, Vienna, Australia.
2. Backward vertical linkages of foreign manufacturing affiliates: evidence from Japanese multinationals;Belderbos;World Development,2001
3. Heum, P., 2008. Local Content Development—Experiences from Oil and Gas Activities in Norway, Study by SNF-Project No. 1285, 02/08 (August).
4. Heum, P., Quale, C., Karlsen, J.E. Kragha, M., Osahon G., 2003. Enhancement of Local Content in the Upstream Oil and Gas Industry in Nigeria: A Comprehensive and Viable Policy Approach. Joint Study by SNF-Institute for Research in Economics and Business Administration, Bergen, Norway SNF Report No. 25/03(August).
5. Morris, M., Kaplinsky, R., Kaplan, D., 2011. Commodities and Linkages: Meeting the Policy Challenges. MMCP Discussion Paper No. 14, October.