Three papers giving introductions to aspects of the antiquarian book trade and definitions used:
"Terms of the Trade" by Roger Gaskell (2000, revised in 2003 with minor corrections in 2006)
"Modern First Editions", a definition (2005, revised in 2006)
"Coming to terms with Mss" by Roy Davids (2003, revised in 2005)
"ABC for Book Collectors" by John Carter and revised by Nicolas Barker, 2004
ILAB Dictionary of bookselling terms: English, French, Italian and German