Ballast, David Kent
McGraw-Hill, 1994
Buku Referensi
edited by John A. Havers and Frank W. Stubbs, Jr.
McGraw-Hill, 1971
Buku Referensi
Timber Engineering Company
F.W. Dodge Corp., 1956
Buku Referensi
King, Reno C.
McGraw-Hill, 1967
Buku Referensi
Shan K. Wang
McGraw-Hill, 1993
Buku Referensi