Gaya APA
BECK, F, B. (1984).
SINKHOLES: THEIR GEOLOGY, ENGINEERING AND ENVIRONMENTAL IMPACT .
Netherlands:
A.A BALKEMA PUBLISHERS.
Gaya MLA
BECK, F, BARRY.
"SINKHOLES: THEIR GEOLOGY, ENGINEERING AND ENVIRONMENTAL IMPACT".
Netherlands:
A.A BALKEMA PUBLISHERS,
1984.
Text.