Gaya APA
R, L., Stewart, . (1990).
Advances In Soil Science: Volume 11 Soil Degradation .
New York:
Springer-Verlag Berlin Heidelberg.
Gaya MLA
R, Lal., Stewart, .
"Advances In Soil Science: Volume 11 Soil Degradation".
New York:
Springer-Verlag Berlin Heidelberg,
1990.
Text.