British art experts hope to solve a mystery surrounding the commissioning of an early 20th century Australian landscape painting.
Dated 1904, the picture by Australian artist John Stirling Moore portrays a prospecting expedition into the interior of Australia and shows tents and trekking camels.
The expedition was funded by the South Australian government.
While a typed letter accompanies the work naming Stirling Moore as its creator, there is no indication of whether the artist travelled alongside the explorers or who commissioned the work.
The note, signed by "Edith" in October 1931, refers to her grandfather having commissioned the painting and wanting it given to "Walter".
The note refers to a photographer - geologist and anthropologist, Herbert Basedow - having joined the expedition and it is possible Stirling Moore used the resultant images to create the painting.
Many of Basedow's photographs are housed in the National Museum of Australia.
The work is to be offered for sale at auction in London on Tuesday.
But auctioneer William Axon of Rowley's Fine Art said a few vital pieces of information about it are still missing.
"We are really hoping that someone in Australia will be able to solve the mystery for us," he said.