Locke, John L.
Simon & Schuster, 1998
Buku Teks
Cambridge University Press, 1996
eBooks
by Bernard Bloch, George L. Trager
Baltimore, 1942
Buku Referensi
by Hanna Fricke
Fakultas Ilmu Pengetahuan dan Budaya Universitas Indonesia, 2017
Artikel Jurnal
Hulsey, Nathan
Emerald Publishing Limited, 2020
eBooks