"Paper presented to the International Fertiliser Society at a Conference in Cambridge, on 6th December 2007, organised with the International Potash Institute and Sabanci University."
OBNB doesn't sell books, but you may be able to find a copy at one of these websites:
Potassium, magnesium and soil fertility : long term experimental evidence by A. E. Johnston. ISBN 9780853102502. Published by International Fertiliser Society in 2007. Publication and catalogue information, links to buy online and reader comments.
