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The International Union of Pure and Applied Chemistry (IUPAC) and the International Union of Pure and Applied Physics (IUPAP) established a working group to clarify the discovery of new chemical elements, particularly the transfermium elements. The group, led by Chairman D. H. Wilkinson and Secretaries A. H. Wapstra and I. Ulehla, aimed to establish criteria for recognizing the discovery of a new element. The discovery of new elements has become complex due to the need for advanced nuclear physics equipment and the short half-life of many isotopes. The working group's report outlines the criteria for recognizing a new element, which will be applied to the discovery of transfermium elements in a subsequent report. The criteria are necessary due to disagreements over the discovery of elements beyond Z=101, which have been made using complete-fusion/neutron-evaporation reactions with low yields.