Gudykunst, William B
Communicating with strangers
McGraw-Hill, 1992
Buku Teks
Hilliard, Elizabeth
Windows and doors
Conran Octopus Lim, 1996
Buku Referensi
Shadbolt, Maurice
Strangers and journeys / Maurice Shadbolt
Hodder and Stoughton, 1972
Buku Teks
Doyle, Roddy
The woman who walked into doors
Penguin Books, 1996
Buku Teks
Hall, John W.
Twelve doors to Japan
McGraw-Hill, 1965
Buku Teks