The orientation of the paintings in the photograph is not correct.
The painting "Abstract Painting - Grey," dated 1950, is owned by the Metropolitan Museum of Art, New York. The painting "Untitled" reproduced in the Marlborough Gallery catalog, estate no 37, was done in 1949.
"Ad Reinhardt," New York: Rizzoli in association with Museum of Contemporary Art, Los Angeles and Museum of Modern Art, New York, 1991, "Abstract Painting -Grey," pg. 24, plate 54.
"Ad Reinhardt: Early Works," New York: Marlborough Gallery, 1999, "Untitled" is no. 47.