c1 Refereed Journal Article.  Lyn 27/1/14.
Yellow in Sherpa: Author's Pre-print:   author can archive pre-print (ie pre-refereeing) 
Author's Post-print:   subject to Restrictions below, author can archive post-print (ie final draft post-refereeing) 
Restrictions: •2 years embargo
Publisher's Version/PDF:   author cannot archive publisher's version/PDF.
Published in Aug 2012. Requested (Keith) Accepted v & permission, 22.9.14-MMM