Gaya APA
The Indonesian Jounal of Geography Vol. 20 No.60 December 1990
.
().
Yogyakarta, Indonesia:
Gadjah Mada University.
Gaya MLA
The Indonesian Jounal of Geography Vol. 20 No.60 December 1990
.
.
Yogyakarta, Indonesia:
Gadjah Mada University,
.
.