Filtering by: Subject antarctica--aerial exploration Remove constraint Subject: antarctica--aerial exploration Subject hearst, william randolph, 1908 Remove constraint Subject: hearst, william randolph, 1908 Subject airplanes Remove constraint Subject: airplanes Time Period (Topic) 1930s (1930-1939) Remove constraint Time Period (Topic): 1930s (1930-1939) Time Period (Topic) 1920s (1920-1929) Remove constraint Time Period (Topic): 1920s (1920-1929)