Friedman, Thomas L.
The world is flat : the globalized world in the twenty-first century
Penguin Book, 2006
 Buku Teks
Bruyn, Severyn T.
A Civil Economy: Transforming the Market in the Twenty-First Century
The University of Michigan Press, 2000
 Buku Teks
Leming, Michael R.
Understanding dying, death, and bereavement
Cengage Learning, 2016
 Buku Teks
Hill, Napoleon
Berpikir dan menjadi kaya=Think and grow rich : for the Twenty-first century / Napoleon Hill; alih bahasa, Arif subiyanto
Ramala Books, 2007
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Parental loss of a child
edited by Therese A. Rando
Research Press, 1986
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