[TOMT] Title of an old picture book
Can you help me find this picture book? It was about a young girl who had to go on a dark journey down a river, it was printed on black paper with white writing and very richly coloured pictures. But it was a proper hardback children's book, at least 18 inches on each side. And the story just ended in the middle, and the rest of the pages, about ten of them, were blank. Blank black. Published at least 50 years ago.
This is all the information I have. Searching on behalf of someone else.