Spirit of enterprise: the 1984 Rolex Awards
Aurum Press, 1984
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Ramon Magsaysay
The Ramon Magsaysay awards : In recognition of greatness of spirit shown in service to the people / Edited by Guilermo S. Santos.. (et al)
Ramon Magsaysay Center, 1985
 Buku Referensi
Montesquieu, Charles de Secondat,1689-1755
The spirit of the laws
Hafner Press, 1949
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Beard, Charles A.
The American spirit
Macmillan, 1942
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Etzioni, Amitai
The Spirit of community
A Touchestone Book, 1994
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