I think this is really a non-issue. Any decent search engine will return hits for your paper, even if one searches for *harmonisation* (the spelling more common in Britain) rather than *harmonization* (the spelling used in the USA, and also valid, though less common, in Britain) as long as a literal search isn't used.

[Example search][1].


  [1]: http://scholar.google.com/scholar?q=harmonisation%20murchan&btnG=&hl=en&as_sdt=0,5