Signed program from the joint performance, New York, 15 May 1977, by the two Broadway legends: the powerful-voiced American actress of stage and film musicals, Ethel Merman, and the beloved American actress and singer, Mary Martin. "Together on Broadway," signed on title-pages. The program, which may be flipped and read from the reverse until mid-point, contains two title-pages, at front and at rear, one listing Merman first, the other listing Martin first (and with commensurate Blackgama "What becomes a Legend most?" fur adverts, featuring each). Merman signed her title-page at upper left, Martin inscribed hers at middle left, in light blue ink: "Happy Birthday / Love / Mary Martin." Includes two ticket stubs and a cardstock menu for the associated Buffet Supper for the "Benefit of the The Theatre and Music Collection of the Museum of the City of New York," including such dishes as  "Tramp Steamship Roast with 'South Pacific' Sauce" and "Annie Oakley's Chili - Red, Hot, and Blue"!  4to, printed wrappers, stapled. Very fine.