Randall, David
The Universal journalist
Pluto Press, 2007
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Wechler, Wolfgang
Universal algebra for computer scientists
Springer-Verlag , 1992
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Hankes, Elmer Joseph
A universal second language
Hankes Foundation, 1992
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Storytelling the Universal language
Artikel Jurnal
Kaelany H.D.
Islam agama universal
Midada Rahma Press, 2006
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