François-Louis Gand Le Bland Du Roullet
François-Louis Gand Le Bland Du Roullet (10 April 1716 in Normanville – 2 August 1786 in Paris) was a French diplomat and playwright. He is chiefly remembered today as the librettist of Gluck's operas ''Iphigénie en Aulide'' and ''Alceste'' (1776 French version). He also co-wrote (with Louis-Théodore de Tschudi) the libretto for Salieri's opera ''Les Danaïdes''. Provided by Wikipedia-
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