BBC- "A rare copy of John James Audubon's Birds of America, billed as the world's most expensive book, is to go on sale at Sotheby's, it has been announced. Only 119 complete copies of the 19th-century book are known to exist, and 108 are owned by museums and libraries. A separate edition of the wildlife book sold for a record-breaking price of $8.8m (£5.7m) a decade ago. The copy going under the hammer in December comes from the collection of Lord Hesketh. It contains 1,000 life-sized illustrations of almost 500 breeds. It took wildlife artist John James Audubon 12 years to complete his study. He did so by travelling across America, shooting the birds. He would then hang them on bits of wire to paint them. The artist then went to Britain to print the volumes and targeted the rich to buy copies"