Norway. (Sudan - Nigeria). 1937. Air Mail addressed to Plateau Province, Northern Nigeria bearing Norway Yvert 84, 1k green, Yvert 121, 40 ore grey (pair) and Yvert 131, 30 ore blue tied by Lillehammer double ring '14th June 37' with 'Med Luftpost' label, routed via Berlin-Zentralflughafen '15/6' and Sudan Air Mail/ Khartoum '18th June', Kano (Nigeria '25th June, Kaduna Junction and Kaduna North '24 Ju' and Kafanchan arrival '25th June' on reverse.
The main Air Mail service in 1937 to Nigeria was via Sudan.