For his String Quartet, Lutosławski had produced only the four instrumental parts, refusing to bind them in a full score, because he was concerned that this would imply that he wanted notes in vertical alignment to coincide, as is the case with conventionally notated classical ensemble music. The LaSalle Quartet, however, specifically requested a score from which to prepare for the first performance. Bodman Rae relates that Danuta Lutoslawska solved this problem by cutting up the parts and sticking them together in boxes (which Lutosławski called "mobiles"), with instructions on how to signal in performance when all of the players should proceed to the next mobile. In his orchestral music, these problems of notation were not so difficult, because the instructions on how and when to proceed are given by the conductor.