Gaya APA
P.E., A, D, P. et al (1984).
Planning and Estimating Heavy Construction .
united states of AMERICA:
McGraw Hill Book Company.
Gaya MLA
P.E., ALBERT, D., PARKER,. et al.
"Planning and Estimating Heavy Construction".
united states of AMERICA:
McGraw Hill Book Company,
1984.
Text Book Sipil.