Gaya APA
Sinukaban, N.
(2007).
Soil and water conservation in sustainable develovement
.
Jakarta:
Dirjen RLPS Dephut.
Gaya MLA
Sinukaban, Naik.
"Soil and water conservation in sustainable develovement".
Jakarta:
Dirjen RLPS Dephut,
2007.
Textbook.