- The phrase "Old Penny" often refers to the predecimalisation coinage in the UK, which was taken out of circulation in 1971. Although Aldwych remained a functioning Underground station until 1994, not all of the platforms were open, some having been shut since World War 2. This might explain why an "old penny" would still be accepted in a ticket machine.
- At the opening of the Underground the fares ranged from 6d (6 old pennies) to 3d one way, and from 9d to 5d for return trip.  It is possible that the type of ticket Lara bought was a cheaper "platform ticket" which allowed station access but not train travel.
- http://en.wikipedia.org/wiki/Decimal_Day Reitrieved on Oct 31st 2008.
- http://www.loyno.edu/~history/journal/1989-0/ladart.htm Retrieved on Oct 31st 2008.