The theft of the 1933 first edition Beck pocket Underground map has been registered with the Metropolitan Police's Stolen Art database and the Antiquarian Booksellers Association has been alerted.
It was stolen from the saleroom of Transport Auctions of London in Croydon in February.
The auctioneer believes it was taken during the viewing period on the morning of the February 17 sale, unbeknown to the auctioneer at the time, who proceeded with the sale of the lot with the hammer coming down at £3200.
Michael Wickham from the auction house said: "We are very distressed to have suffered our first-ever loss at one of our sales and sad to have let down our internet buyer who, of course, thought he had won this wonderful map, just as we did."
Wickham said the map is identifiable by Beck's signature and a small ink-spot and a faint trace of a pencilled date on the cover.
If anyone has information they can contact the police using the crime reference no 3806411/18.
