After a research-intensive journey that involved our readers, historians, archivists, writers and curators in the United States and France — and even the former Rolling Stones bass guitarist (and accomplished photographer) Bill Wyman — City Room can confirm that an unidentified and undated photograph from the archives of the Port Authority of New York and New Jersey depicts Marc Chagall and his second wife, Valentina Brodsky, known as Vava. The identification of the photograph comes from Bella Meyer and Meret Meyer Graber, Chagall’s granddaughters from his first wife, Bella Rosenfeld.

Three weeks ago, to mark the 60th anniversary of John F. Kennedy International Airport, City Room posed a pop quiz, asking readers to identify people shown arriving on the tarmac with fanfare in four photographs supplied by the Port Authority, which runs the airport.

The Port Authority’s archives were mostly destroyed on Sept. 11, 2001, but based on its preliminary identifications, we originally named a winner of the pop quiz: Sharon, who guessed that the photos depicted the Israeli statesman David Ben-Gurion and his wife, Paula, along with Jimmy Durante, Sammy Davis Jr. and wife May Britt, and Kim Novak.

But a sharp-eyed Times editor insisted that the picture was not of the Ben-Gurions, and Howard M. Sachar, a renowned historian of Israel who met the Ben-Gurions on multiple occasions, agreed....