W. Unger was an artist who made an etching after this portrait in W. Unger and W. Vosmaer, Etchings after Franz Hals (Leyden, 1873).
 Karl Woermann, Wissenshaftliches Verzeichnis der älteren Gemälde der Galerie Weber in Hamburg (Dresden, 1907), p. 186–87, no. 223
 Wilhem R. Valentiner lists the painting (Frans Hals, Klassiker der Kunst [Stuttgart, 1923], p. 314, no. 124, pl. 124) as “Früher in der Sammlung Wever in Hamburg” [formerly in the Weber collection], but does not give current status. Presumably it sold in the 1912 auction.
 Sale price per Seymour Slive (Frans Hals, 3 vols. [London, 1970], 3:56–57, no. 100, and 2:pl. 158).
 Valentiner, 1923, has the painting with Herzog. The business records of the dealer Duveen, now on microfilm at the Getty Research Institute, contain additional references: Box 248, reel 103 includes 5 items dated 1929 referring to the “Portrait of a Man” by Hals in the Herzog collection, Budapest.
 Wilhem R. Valentiner (Frans Hals Paintings in America [Westport, Connecticut, 1936], no. 46, ill.) has the painting at Wildenstein, as does G. D. Gratama (Frans Hals [The Hague, 1943; 2nd ed., 1946], pp. 39, 55, no. 48, pl. 48). Gratama’s 2nd edition includes a forward in which he explains that the first edition was written in 1938, with publication delayed by World War II. Gratama must have had little or no current information regarding work in America while preparing the 2nd edition in The Hague during the war.
 Acquired from Wildenstein, July 25, 1955. Date per Slive, 1970
The Art Loss Register has recommended further investigation of the painting’s provenance through Hungarian authorities, due to the fact that portions of the Maurice L. Herzog collection were looted during the Nazi era. However, the painting is well documented in the United States as early as 1933. While the painting was exhibited in Haarlem, The Netherlands, briefly in 1937, it was again on view in New York by November of that year. Furthermore, authoritative authors (Valentiner, Gratama) place the painting at Wildenstein, New York, in 1936, 1938, and possibly again in 1943–46. Although details of the painting’s ownership during this period are not yet confirmed (for example, was it consigned to Wildenstein, or sold?), its presence in the United States from 1933 onward must have placed it out of harm’s way with respect to Nazi looting. The painting was acquired from Wildenstein by the Putnam Foundation in 1955. To date there is no evidence that it was outside the United States during World War II. At the present time, there is no reason to believe that this painting was looted either in Budapest or France.