Surakarta, 25 en 26 December 1919.Weltevreden, Albrecht, 1921
Buku Teks
Peacock, James
Prentice-Hall, 1980
Buku Teks
Bakker, Jaap
Bert Bakker, 1993
Buku Teks
Maurois, A. (Andre)
[T.t.] Gallimard 1927
Buku Teks
United Nation. Departement of Economic and Social Affairs. Statistical Office
United Nation, 1957
Buku Referensi