Ratzan, Lee, author
American Library Association, 2004
Buku Teks
Locke, John L.
Simon & Schuster, 1998
Buku Teks
Potter, Andrew, author
Harper Perennial, 2011
Buku Teks
Sarah Farisah Halim Kalla, author
Fakultas Ekonomi dan Bisnis Universitas Indonesia, 2019
UI - Tugas Akhir
Spiller, Neil, author
Academy Group, 2001
Buku Teks