ALL, DOING RESEARCH ON RADIO MANUFACTURERS & TRADE NAMES. WOULD LIKE TO BORROW ANY ISSUE 1927 THRU 1931 OF THE LISTED PUBLICATION . WOULD LIKE TO XEROX THE FOLLOWING NAME / ADDRESS = SECTIONS: SETS CRYSTAL , SETS KNOCKDOWN , SETS PHONOGRAPH/RADIO & SETS VACUUM TUBE.=20 THANKS, STEVE