Nigerian Journal of Engineering - Zaria, Nigeria. Fac. of Engineering, ABU - 14(2), 2008; 15(2), 2008; 16(1), 2009; 17(1), 2010; 18(1), 2011; 16(1), 2009; 19(2), 2012; 20(1), 2013; ISSN: 0794-4756 LC Class. No.: T1 / .N54