A leading Chinese mathematician Yang Le said Sunday that the successful unraveling of one of the world's toughest puzzles is an outstanding job.

Two Chinese mathematicians, Zhu Xiping and Cao Huaidong, have put the final pieces together in the solution to the puzzle that has perplexed scientists around the globe for more than a century.

The pair have published a paper in the latest US-based Asian Journal of Mathematics, providing complete proof of the Poincare Conjecture promulgated by French mathematician Henri Poincare in 1904.

A Columbia professor Richard Hamilton and a Russian mathematician Grigori Perelman have laid foundation on the latest endeavors made by the two Chinese. Prof. Hamilton completed the majority of the program and the geometrization conjecture.

Yang, member of the Chinese Academy of Sciences, said in an interview with Xinhua News Agency, "All the American, Russian and Chinese mathematicians have made indispensable contribution to the complete proof."

Prof. Zhu at Guangzhou-based Zhongshan University and Prof. Cao at Lehigh University in Pennsylvania co-authored the 300-page paper, "The Hamilton-Perelman Theory of Ricci Flow-The Poincare and Geometization Conjecture," which was published in the June issue of the journal.

"The total length of Perelman's work on the conjecture by the end of 2002 was about 70 pages," said Yang, citing that Perelman raised guidelines for proving the conjecture but not specifically pointed out how to unravel the puzzle.

"Guidelines are totally different to complete proof of theories," Yang said.

(Xinhua News Agency June 5, 2006)