Section drawing of office tower project in Philadelphia by Louis I. Kahn and Anne Tyng, 1952-7

616-foot-tall office tower project in Philadelphia designed by Louis I. Kahn and AnneTyng between 1952 and 1957 "could be considered a precursor, given [Renzo] Piano's apprenticeship in that office, [of] the Centre Pompidou [in Paris, 1971-5, designed by Renzo Piano and Richard Rogers, that] clearly initiated the production-oriented practices that followed in Europe, both in its architects' work and in that of Norman Foster."