Gaya APA
PETRIE, G., KENNIE, T.
(1991).
TERRAIN MODELLING IN SURVEYING AND CIVIL ENGINEERING
.
New York:
MC GRAW HILL.
Gaya MLA
PETRIE, G.., KENNIE, T.J.M..
"TERRAIN MODELLING IN SURVEYING AND CIVIL ENGINEERING".
New York:
MC GRAW HILL,
1991.
Text.