Gaya APA

Wirakusumah, A, D. (1991). Some Studies of Volcanology, Petrology and Structure of Mt. Kelut East Java Indonesia . Wellington: Victoria University.

Gaya MLA

Wirakusumah, Achmad, Djumarma. "Some Studies of Volcanology, Petrology and Structure of Mt. Kelut East Java Indonesia". Wellington: Victoria University, 1991. Text.