"1867 04 28." . . . . . . . . "Saying that owing to wholly unforeseen circumstances he has signed a contract with the Opéra for a major work [Hamlet] which he has had on his hands for the past six years, adding that although he had wanted to collaborate with Labiche he cannot do so now, mentioning Delacour, etc."@en . "[n.p., Paris?], 28 April 1867, to M. [Eugène] Labiche"@en . . .