Samuel, Myra L.
Pearson - Prentice Hall, 2003
Buku Teks
Remington, Richard D.
Prentice Hall Inc., 1985
Buku Teks
Dunn, Olive Jean
John Wiley & Sons, 1977
Buku Teks
Daniel, Wayne W.
John Wiley & Sons, 1983
Buku Teks
Daniel. Wayne W.
John Wiley & Sons, 1999
Buku Referensi