Gaya APA
Rock, N. (1983).
Geologi lembar Lubuksikaping, Sumatra = The geology of the Lubuksikaping Quadrangle, Sumatra .
Bandung:
Geological Research and Development Center.
Gaya MLA
Rock, N.M.S..
"Geologi lembar Lubuksikaping, Sumatra = The geology of the Lubuksikaping Quadrangle, Sumatra".
Bandung:
Geological Research and Development Center,
1983.
Text.