His uncle was the art historian Henry Thode, with whom he studied in Heidelberg and under whom he wrote his dissertation, published in 1900 as Die Genredarstellungen Albrecht Dürer.
His research there resulted in his 1905 book on Florentine Trecento painting, Florentinische Maler um die Mitte des XIV Jahrhunderts.
He became an expert on Raphael, Bramante, da Vinci, and Titian ("his favorite until the end"[1]), and also on various regional schools of Italian painting, especially Ligurian, Lombard, and Venetian art.
In 1999 their son-in-law and daughter, Kurt and Alessandra Manning Dolnier, made a partial gift of the Suida-Manning Collection to the Blanton Museum of Art at the University of Texas at Austin.
[6][7] According to the New York Times, major works in the collection include The Conversion of St. Paul, painted by Daniele Crespi about 1621, considered to be the artist's finest painting in the United States; Sebastiano del Piombo's Portrait of a Man from about 1516, a rare example of a High Renaissance portrait; Sebastiano Ricci's mythological Flora, c. 1712–1716; a very early work by Claude Lorrain, Pastoral Landscape, from 1628–1630; and Tiepolo's Storyteller, from the mid-1770s, part of a famous series depicting 18th-century Venice.
[9][10] The collection also includes works by Rubens, Boucher, Correggio and many other Italian, French, German, Austrian, Dutch, and Flemish artists of the 14th to the 18th centuries.
[11] In 1999 Kurt and Alessandra Manning Dolnier made a partial gift of the Suida-Manning Collection to the Blanton Museum of Art at the University of Texas at Austin.