Sawyer, R. Keith, author
L. Erlbaum Associates, 1997
Buku Teks
Symon, Keith R.
Addison-Wesley, 1971
Buku Teks
Sitepu, Sri Rosma Kencana, author
Fakultas Ilmu Keperawatan Universitas Indonesia, 2023
UI - Tesis Membership
Twain, Mark, 1835-1910, author
Random House, 1991
Buku Referensi
Twain, Mark, 1835-1910, author
Kepustakaan Populer Gramedia, 2016
Buku Teks