Gaya APA

Keats, W. (1981). Geologi lembar Lhokseumawe, Sumatra = The geology of the Lhokseumawe Quadrangle, Sumatra . Bandung: Geological Research and Development Center.

Gaya MLA

Keats, W.. "Geologi lembar Lhokseumawe, Sumatra = The geology of the Lhokseumawe Quadrangle, Sumatra". Bandung: Geological Research and Development Center, 1981. Text.