A book owned by Harvard University has been been bound in human skin, scientists believe.
Des destinees de l'ame (Destinies of the Soul) has been housed at Houghton Library since the 1930s.
Writer Arsene Houssaye is said to have given the book to his friend, Dr Ludovic Bouland, in the mid-1880s.
Dr Bouland then reportedly bound the book with skin from the body of an unclaimed female mental patient who had died of natural causes.
"The analytical data, taken together with the provenance of Des destinees de l'ame, make it very unlikely that the source could be other than human," Bill Lane, the director of the Harvard Mass Spectrometry and Proteomics Resource Laboratory, told theHoughton Library Blog.
The practice of binding books in human skin - termed anthropodermic bibliopegy - has been reported since as early as the 16th Century.
Numerous 19th Century accounts exist of the bodies of executed criminals being donated to science, their skins later given to bookbinders.
Located within Des destinees de l'ame is a note written by Dr Bouland, stating no ornament had been stamped on the cover to "preserve its elegance".
"I had kept this piece of human skin taken from the back of a woman," he wrote. "A book about the human soul deserved to have a human covering."
The book, said to be a meditation on the soul and life after death, is believed to be the only one bound in human skin at Harvard.
Comparable tests undertaken on books at the university's law and medical school libraries revealed books bound in sheepskin.