Thanks to all who replied, I opted to go with Patrick Drechsler
solution of installing the underscore.sty package for the time being
but may well end up trying Roger Bivand's solution if at any stage I
wish to include subscripts in my main text (which I can envisage).
Thanks for the rapid and useful responses,
Regards
Neil
--
"Once, adv. - Enough
Twice, adv. - Once too often"
- Ambrose Bierce, The Devil's Dictionary
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