In message , at 11:19:04 on Mon,
30 Jun 2008, Paul Terry remarked:
ZSL stated that they needed TWO *paper* tickets from 'outside' London
to London - although they couldn't define the term 'outside' nor the
exact destination London station required.

The terms and conditions state that all you need are two paper tickets
with the National Rail symbol printed on them, valid for the date of
admission to the attraction, which it appears you had.

Two such paper tickets issued to the same traveller seems to me to be
outside the spirit of the rules.

--
Roland Perry