in  johnson entered a new phase of his career founding a partnership with architect john burgee johnson and burgee won commissions for a series of new skyscrapers including the ids center in minneapolis  and the two matching towers facing each other like bookends of pennzoil place in houston texas the two towers of pennzoil place have sloping roofs covering the top seven floors and are trapezoidal in form created to leave two large triangual aras on the site which are occupied with glass-covered lobbies designed like greenhouses this idea was widely copied in skyscrapers in other cities