An early work by Charles Blackman and a large painting of the Olgas by influential British artist Michael Andrews are highlights of a sale of modern and post-war British art at Sotheby's in London on June 13.

Blackman's Two Friends dates from 1961, the year of the artist's first solo exhibition in London. Consigned to auction from a prominent UK collection, it dates from his visit to London, courtesy of a Helena Rubenstein scholarship, to participate in the landmark exhibition "Recent Australian Painting" at the Whitechapel Gallery. His work was shown alongside paintings by Sidney Nolan, Arthur Boyd and Brett Whiteley. Apparently curator Bryan Robertson was so impressed he arranged a solo exhibition for Blackman at the Matthiesen Gallery later that year.