WHAT NEW YORK CITY BUILDING DID GUNVALD AUS AND CASS GILBERT WORK ON TOGETHER?
Gunvald Aus: Gunvald Aus, also written Aas (May 30, 1851 – May 27, 1950) was a Norwegian-American engineer. Gunvald Aus:  He is most associated with the engineering of the Woolworth Building in New York City. Woolworth Building: The Woolworth Building, at 233 Broadway, Manhattan, New York City, designed by architect Cass Gilbert and constructed between 1910 and 1912, is an early US skyscraper.
Woolworth Building