Elliott, Osborn
Men at the top
Harper & Brothers , 1959
Buku Teks
Ziglar, Zig
Steps to the top
Heinemann Asia, 1995
Buku Teks
Unsaturated soil
ASCE, 1993
Buku Teks
Craig, R.F. (Robert F.)
Soil mechanics
Chapman & Hall , 1992
Buku Teks
Sulman, Elizabeth
Introduction to soil
Prentice-Hall, 1999
Buku Teks