Rob, Golding
Mini thirty-five years on
The Bath Press, Avon, 1994
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Cambridge, Ada. 1844-1926
Thirty years in Australia / Ada Cambridge
New South Wales University Press, 1989
 Buku Teks SO
Hu, Chiao-Mu
Thirty years of the communist party of China
Foreign Languages Press, 1952
 Buku Teks SO
China and New Zealand : a thriving relationship thirty years on
edited by James Kember
New Zealand Asia Institute, 2003
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Statistics of centuries : statistical curios in Hungarian history
The Hungarian Central Statistical, 2002
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