books%3Fid=aygDAAAAMBAJ&pg=PA24&dq=Popular+Science+1931+plane&hl=en&ei=kmIMTcOYN5OBnAfj_I2WDg&sa=X&oi=book_result&ct=result&resnum=8&ved=0CEEQ6AEwBzgK%23v=onepage&q&f=true
books%3Fid=aygDAAAAMBAJ&pg=PA24&dq=Popular+Science+1931+plane&hl=en&ei=kmIMTcOYN5OBnAfj_I2WDg&sa=X&oi=book_result&ct=result&resnum=8&ved=0CEEQ6AEwBzgK%23v=onepage&q&f=true