Gaya APA

Wirakusumah, A, D. (1991). Some Studies Of Volcanology, Petrology And Structure Of Mt. Kelud, East Java, Indonesia . Bandung, Jawa Barat, Indonesia: Univ. of Welington.

Gaya MLA

Wirakusumah, Achmad, Djumarma. "Some Studies Of Volcanology, Petrology And Structure Of Mt. Kelud, East Java, Indonesia". Bandung, Jawa Barat, Indonesia: Univ. of Welington, 1991. Text.