They set up their own practice in 1885 and were key proponents of French and Beaux-Arts style architecture in the 1890's, later designing the main branch of the New York Public Library, the Standard Oil Building and major residences like the Frick mansion.

Later projects included the Frick mansion at 70th Street and Fifth Avenue.

The private apartments for the Frick mansion and the 30-room duplex of Conde Nast were among the interiors she designed.

The two volumes, with contributions from Mark Alan Hewitt, Kate Lemos, William Morrison and Charles D. Warren, naturally pay great attention to the men's best-known commissions in New York, like the Frick mansion and the New York Public Library.

The wing, to be named for Nancy and the late Frederick DeMatteis, who gave $2 million, will be erected on land east of the Frick mansion and will also be two stories high.

The new structure will also provide space to display more of the museum's permanent collection in the Frick mansion and increase educational programming, he said.

Tomorrow and Sunday at 2:45 p.m., "Old and New Money: The Origins of Fifth Avenue and Central Park West," with stops at historic buildings like the Dakota and the Prasada, as well as the Payne Whitney and Frick mansions.

I believe there is the Frick mansion, and I can't think of another one.

Unfortunately, the Frick mansion is ill-suited for the type of exhibitions recently mounted, when a fraction of the cost is needed for installation, security, climatization and necessities dictated by decorative art.