DagnyTaggart hears BrakemaN whistling the theme of a concerto. When she asks him what piece it's from, he says HalleysFifthConcerto. When Dagny points out RichardHalley? only wrote four concertos, BrakemaN claims he made a mistake and he doesn't recall where he heard the piece.
Part 1, Chapter 1, section 2 (AtlasShrugged112) Part 1, Chapter 1, section 3 (AtlasShrugged113)