Staples, 1970
Buku Teks
Bearden, James H., author
Holt, Rinehart and Winston , 1969
Buku Teks
Din, Rasshied, author
Conran Octopus, 2000
Buku Teks
Din, Rasshied, author
Conran Octopus, 2000
Buku Referensi
Nau, Henry R., 1941-, author
SAGE Publications, 2019
Buku Teks