Kwajaffa, Bitrus F., Mohammed A. Audu, and Hauwa A. Yamta. “Effective Planning And Techniques Of Successful Negotiation And Purchasing In An Organisation”. International Journal of Creativity and Technical Development (IJCTD) 1, no. 1-3 (June 1, 2009): 92–105. Accessed September 19, 2024. http://icidr.org.ng/index.php/Ijctd/article/view/689.