Piero della Francesca
Whilst establishing himself as a notable Caravaggio scholar, Longhi retained a lively interest in Piero della Francesca, editing a monograph in 1928, representing him as the leading painter of the Quattrocento. Longhi believed Piero della Francesca played a decisive role in the development of Venetian painting. This monograph, which Kenneth Clark opined could hardly be improved upon, established itself as a classic of art-historical literature.