After the Allies reached Paris in 1944, she guided the Monuments Men in their searches. Simon and Nick Goodman saw from their father's records that Valland or her associate, Albert Henraux, personally had transferred three paintings to Bernard Goodman and his sister, who's now 94 and living in Italy.

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Initially working from a list of their parents' major paintings they had compiled from memory, brother and sister also filed claims with the Dutch government. That bore some fruit, but Simon and Nick Goodman's later research showed that authorities held back about half of the Gutmann holdings the Monuments Men had sent to Holland.

Even the restitution Bernard Goodman received leaves a bad taste for Simon: He said the Dutch government insisted that his father pay off the mortgage and taxes on the family estate — debts accrued after 1943, when the Nazis arrested his grandparents, sent them to Theresienstadt and expropriated their home. Fritz Gutmann was beaten to death, after which his wife was transferred to Auschwitz and gassed.

Also dubious, Simon said, were exorbitant expense reimbursements his father had to pay to trustees a Dutch court had appointed to take charge of the family's holdings while he and his sister tried to prove that their parents were in fact dead, and they the legal heirs.

One of the works that passed from the Monuments Men to the Dutch to Bernard Goodman was "Still Life: Tea Set," a 1780s painting by the Swiss artist Jean-Etienne Liotard that now hangs in the J. Paul Getty Museum, which acquired it in 1984.

The Hals portrait that wound up in San Diego, and a Hieronymus Bosch painting, "The Temptation of St. Anthony," now at the National Gallery of Canada in Ottawa, may have been saved from looting — but nevertheless lost to the family — because Fritz Gutmann had sent them to be shown at an exhibition at the 1939 New York World's Fair.

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A dealer who'd been a party to the loan arrangement sold the paintings without the family's knowledge or direct authorization after the war broke out, Simon Goodman said, but technically he'd been granted an "effective power of attorney," giving him a legal right to proceed. Bernard Goodman found the dealer after the war and received a payment.

"[My father] was very sad about the whole thing," Simon said, recalling the day in San Diego when he had opened up a bit.

As Nick and Simon Goodman took up the search — Nick as lead researcher in the early days, with Simon taking over in the early 2000s, when he sold his business and made the hunt his full-time job — they tapped resources unknown or inaccessible to their father.

The Monuments Men's records, now housed at a National Archives and Records Administration facility in Maryland, became a belated ace, dealt at last to the hand of justice. The Army art specialists had filled out a file card for each art object they'd found and had created transcripts of their interrogations of captured German officers and civilian art dealers who'd worked for the two most prominent Nazi art-lovers — Adolf Hitler and Hermann Goering. Hitler stockpiled looted art for a museum he wanted to establish in his hometown of Linz, Austria.

The art library at UCLA became another resource for the Goodman brothers, who paged through catalogs from exhibitions and art auctions, searching for references to Gutmann holdings. Simon says they soon began to benefit from the Getty Research Institute's enormous trove of original documents about art.

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Their first success — a partial settlement, because of the legal complexities of the claim — was a small pastel landscape by Edgar Degas that a Chicago pharmaceuticals magnate had lent to the Art Institute of Chicago.

The case was grueling and expensive, settled by the businessman, Daniel Searle, in 1998 after a British documentary and CBS' "60 Minutes" had chronicled the brothers' underdog fight. When their money was running out, the Goodmans, media-savvy pros of the entertainment industry, applied pressure and rallied support by placing an appeal for help in a national Jewish publication, the Forward.

As time went on, they tried to do as much as possible themselves, saving the expense of lawyers and investigators. The Internet soon came into its own, and that, the brothers said, has made all the difference. From his cubbyhole office overlooking the swimming pool, brick patio and flowering trees in his Beverly Hills back yard, Simon can access the Nazis' own meticulous files, along with highlights of the Monuments Men archives and much more.

Photographs of brilliant silver and gold tea service vessels that the Goodman brothers tracked down at the Rijksmuseum, the Dutch national museum in Amsterdam, flank the computer on either side. Portraits of their great-grandparents look over Simon's shoulder.

Elsewhere in the house hang separate photographs of his grandparents, taken in 1926 by the American expatriate artist Man Ray. Fritz Gutmann, the very image of a resolute businessman, has the same dark eyebrows as Simon. Louise wears fur and a Garbo-esque mien of glamorous detachment.

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