Cathy Naso received the painting as a reward for her unpaid work
A self-portrait of Andy Warhol that sat in a closet for more than 40 years will be auctioned in New York next month.
The late artist gave the piece to Cathy Naso, a receptionist at his Factory studio, in 1967. She displayed the work briefly, then stored it in a cupboard.
Inscribed by Warhol, it is expected to fetch at least $1m (£604,576) when it is sold at Sotheby's on 11 November.
"I would love to keep it forever, but it really belongs to the art world," Naso told the New York Times.
"I've treasured it, and I want whoever ends up owning it to treasure it too."
According to the New York Times, Brooklyn-born Naso was hired as a receptionist after going to Warhol's studio to interview him for a class assignment.
"I went there with a friend to do an interview, and suddenly we were the ones being interviewed," she told the paper.
When Warhol gave Naso the 1965 self-portrait, she watched him sign it: "To Cathy (2 years late)."
It will be display at Sotheby's New York offices from Friday ahead of next month's auction.
In 2002 a Warhol self-portrait completed a year before his death was sold for more than $3m (£1.8m).