Jähne, Johannes
Leipzig, 1964
Buku Teks
Erwin Frizi
Universitas Indonesia, 2014
UI - Skripsi (Membership)
Owen, Wilfred
Brookings Institution, 1951
Buku Teks
Lay, M.G
Australian Road Research Board, 1985
Buku Teks
Watkins, L. H.
Prentice-Hall, 1981
Buku Teks