Norris, Pippa
Cambridge University Press, 2015
eBooks
Dimas Suryo Sudarso
Kementerian PPN/Bappenas, 2019
Artikel Jurnal
McCarthy, John Joseph, 1909-2005
McGraw-Hill, 1978
Buku Teks
Belbin, R. Meredith
Heinemann, 1983
Buku Teks
Levy, Matthys
W.W. Norton & Co., 1992
Buku Teks