A self-portrait by Frida Kahlo could best the artist's auction record when it is offered by Sotheby's in New York this November. Should it sell near its low estimate, it will achieve the artist's highest price at auction. El Sueňo is one of a number of gems from a major private collection to have been consigned to the November sale, Sotheby's announced today. Every work announced by Sotheby's today was exhibited at this Guggenheim show as part of the Nesuhi Ertegun collection. The Mica Ertegun collection was sold at Christie's New York last year, led by Magritte’s L'empire des lumières (1954), which broke the artist's record, making $121.m (with fees).