NEW YORK, NY.- J.C. Leyendecker’s striking Lovebirds, The House of Kuppenheimer Style Book advertising diptych, Fall/Winter 1918-1919, is expected to bring more than $80,000 to lead the offerings in Heritage Auctions‘ May 4 Signature(r) Illustration Art Auction at the Fletcher-Sinclair Mansion (Ukrainian Institute) at 2 East 79th Street (at 5th Ave). This simply superb example represents peak period work from one of the greatest painters from the Golden Age of Illustration. “This masterpiece has been in a single collection since the 1920s and has never before been offered on the market,” said Todd Hignite, Consignment Director for Heritage Auctions. “Frankly, in our continued search for the absolute best in Illustration Art, this is exactly the kind of painting we dream about uncovering.” Following the resounding success of Heritage’s $4.1 million February auction in Beverly Hills, the diverse highlights of the auction are a testa