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Dyfyniad Arddull ChicagoJONES, Edward. Paradox 4 Made Easy. Berkeley: Osborne McGraw-Hill, 1992.
Dyfyniad MLAJONES, Edward. Paradox 4 Made Easy. Osborne McGraw-Hill, 1992.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.