Tolong jelaskan mengenai Rujukan dari Pentadbiran Pos Pertubuhan Bangsa-Bangsa Bersatu dalam bahasa melayu

Conway, Herbert. 25 years of philatelic highlights. New York: United Nations Postal Administration, 1976, 59p.

Gaines, Arleigh. United Nations Philately. New York: R.& D. Publications, 1980-1997, 3 vols.

Goody, Ramon. A study of the first United Nations regular and airmail postage stamps, 1951-1966. Chelmsford: The Author, 1978, 120p.

Kelen, Emery. Stamps tell the story of the United Nations. New York: Meredith Press, 1968, 95p.

Michel UNO-Spezial-Katalog 2012. München: Schwaneberger Verlag, 2011 , 544p.

Patrick Douglas and Mary. The postage stamps and postal history of the United Nations. Toronto: Ryerson Press, 1955, 174p.