Usman,{et.all}, A. et al.(1987).Electrical wiring Commercial Based On the 1987 National Electrical Code (keenam).United States of America:Delmar Publ.Inc..
Gaya MLA
Usman,{et.all}, A. et al..Electrical wiring Commercial Based On the 1987 National Electrical Code.keenamUnited States of America:Delmar Publ.Inc.,1987.Text.