John Hartley [and others]
Rinehart and Winston, 1962
Buku Teks
by Taylor, Barbara... [et al.]
McGraw-Hill, 1995
Buku Teks SO
by Taylor, Barbara... [et al.]
McGraw-Hill, 1995
Buku Teks SO
Rubin Dorothy
CBS College pblishing, 1982
Buku Teks SO
ILO, 1985
Buku Teks