 Then, in November 2009, a fourth treatise, this time in Charpentier's own hand, was identified in the collection of the Lilly Library at Indiana University, Bloomington, U.S.A.Written during the final months of 1698 and numbered "XLI," this treatise appears to have been the forty-first in a series hitherto not imagined by Charpentier scholars, a series of theoretical treatises that spans almost two decades, from the early 1680s to 1698.The prelude to his Te Deum, H. 146, a rondo, is the signature tune for the European Broadcasting Union, heard in the opening credits of Eurovision events.