Acrobat Reader

The map refernce work is accessed by a set of PDF  (Portable Document Format) files.
This requires an Acrobat Reader to be installed on your computer.

If you fail to access these files there is a good chance that you do not have Acrobat installed,
or your version of Acrobat is well past its usefulness in the 21st century.

A free and fresh version can be downloaded from