edited by S.J. De Leat, A.H. Dani, J.L. Lorenzo and R.B. Nunoo
Routledge , 1994
Buku Referensi
edited by A.G.L.Shaw, C.M.H. Clark
Melbourne University Press , 1967
Buku Referensi
edited by H.S.W. Massey, E.W. McDaniel, Benjamin Bederson
Academic Press, 1982
Buku Teks
edited by Richard Ivan Downing
Weidenfeld and Nicolson, 1973
Buku Teks
Rand McNally & Company, 1960
Buku Teks