Forty five cards (90 sides) in envelope.
OBNB doesn't sell books, but you may be able to find a copy at one of these websites:
Serpentine Photography 73 : the Arts Council presents work by 43 young photographers [held at the Serpentine Gallery], July 28-August 19 by Serpentine Gallery. ISBN 0900085940. Published by Serpentine Gallery in 1973. Publication and catalogue information, links to buy online and reader comments.
![Serpentine Photography 73 : the Arts Council presents work by 43 young photographers [held at the Serpentine Gallery], July 28-August 19](http://ecx.images-amazon.com/images/I/51dNactFzhL._SL160_.jpg)