An art expert says the discovery of a previously unknown work by Vincent van Gogh is doing for paintings what the tabloids did for sightings of Elvis Presley: suddenly, they're everywhere.

"We've had calls from people who think they have Renoirs, Monets, van Goghs - it's hilarious," said Leslie Hindman, whose auction house in March will sell a van Gogh found in a Wisconsin couple's home.The painting to be auctioned was spotted by a part-time worker at Leslie Hindman Auctioneers. It was declared authentic by senior curators at the Rijksmuseum Vincent van Gogh in Amsterdam - one of the world's greatest collections of works by the 19th century Dutch artist.

Hindman said the van Gogh may bring about $500,000 at auction, even though it is considered a minor work. It is owned by a suburban Milwaukee couple who have asked not to be identified.

Since announcement of the discovery this week, Hindman said, her office has been deluged with calls from people who are sure they, too, have found the real thing.

A Florida man called to say he had several van Goghs, a Rembrandt "and a da Vinci, I think," Hindman said.

Some people who call are being cautious, she said.

"They're really funny: `I'm not going to tell you anything. I'm not going to tell you where I live,' " Hindman said.

Hindman said she plans to check out all of the calls.

But how many claims will be authentic?

"None," she said. "I mean, really, none."