Northern Nigeria (Nigeria). Ministry of Health. Annual report of the Ministry of Health, Northern Nigeria. Govt. Printer.
Dyfyniad Arddull ChicagoNorthern Nigeria (Nigeria). Ministry of Health. Annual Report of the Ministry of Health, Northern Nigeria. Kaduna: Govt. Printer.
Dyfyniad MLANorthern Nigeria (Nigeria). Ministry of Health. Annual Report of the Ministry of Health, Northern Nigeria. Govt. Printer.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.