Rosenberg, Donna
Buku Teks
Gorki, Maxim, author
T. Werner Laurie, [Date of publication not identified]
Buku Teks
Gedes & Grosset, 2001
Buku Referensi
Johnson, George B., author
McGraw-Hill, Higher Education, 2008
Buku Teks
Stanier, Roger Y., author
Prentice-Hall, 1963
Buku Teks