@book{59263,
	author = {Verstappen, H. Theodoor},
	title = {Sumbangan bagi geomorfologi kepulauan Maluku},
	publisher = {Departemen Pertahanan, Direktorat Topografi A. D., Balai Geografi [cover},
	year = {1960]},
	address = {Djakarta,}
}