In 1976, Morton Feldman accepted a commission from the opera in Rome for the opera Neither. The works Orchestra, Elemental Procedures and Routine Investigations, represented a "triology" for Feldman with which he prepared himself for the work on his opera. In all thre epieces, Feldman uses a characteristic complex of material, clearly differentiated from his previous type of textural treatment and inserted as a fixed element into the course of the music.