Wall of Sound but Phil came along and took these to make sounds that had not been used in the past. I thought it was ingenious." During the mid-1950s, Spector worked with Brill Building songwriters Jerry Leiber and Mike Stoller during a period where they sought a fuller sound by the use of excessive instrumentation, using up to five electric guitars and four percussionists. This was later to evolve into Spector's Wall of Sound, which Leiber and Stoller consider to be very distinct from what they were doing, stating: "Phil was the first one to use multiple drum kits, three pianos and so
Axiom of pairing of set theory. Nevertheless, in the standard formulation of the Zermelo–Fraenkel set theory, the axiom of pairing follows from the axiom schema of replacement applied to any given set with two or more elements, and thus it is sometimes omitted. The existence of such a set with two elements, such as { {}, { {} } }, can be deduced either from the axiom of empty set and the axiom of power set or from the axiom of infinity. Together with the axiom of empty set and the axiom of union, the axiom of pairing can be generalised to the