I bought a book some time ago (can't remember what book, but not one of Terry's) which had a section from another book entirely plonked in the middle, with a corresponding slice missing.
I thought I was going daft(er) till I realised the numbering, typeface and the characters were totally foreign.
Took it back to change it and the other copy was the same! They re-ordered it for me.
I wish I was a glow worm, A glow worm's never glum, How can you be unhappy when the sun shines out yer bum?