Gaya APA
Ashford, N, J., Wright, P, H. (1989).
Transportation engineering: planing and design (Ed. 3).
United States of America:
John Willey and Sons.
Gaya MLA
Ashford, Norman, J.., Wright, Paul, H..
"Transportation engineering: planing and design".
Ed. 3
United States of America:
John Willey and Sons,
1989.
Printed Book.