1. Public–private partnerships and contract negotiations: an empirical study
2. Achieving best value in private finance initiative project procurement
3. All Africa (2011). Nigeria: Issues Protests against Lekki Toll Plazas. Available from http://allafrica.com/stories/201112130487.html consulted (05/03/12)
4. How Gauteng has Reaped Benefits of Road Upgrades;Alli N.;Sunday Times,2013
5. Balezdrova A. (2011). Greek drivers refuse to pay toll fees companies concessionaires are looking for a way to collect the lost revenues [online] available from. http://www.grreporter.info/en/greek_drivers_refuse_pay_toll_fees_companies_concessionaires_are_looking_way_collect_lost_revenues/3- consulted: 28 February 2012