\blacksquare and \square do not work in texi2pdf

[Christopher Dimech]

Have noticed that \blacksquare and \square give errors when using texi2pdf.
The commands word when output is html.

The following three commands all fail with texi2pdf

@math{\blacksquare \square}

@displaymath
  \blacksquare \square
@end displaymath

@tex
  $\blacksquare \square$
  $$\blacksquare \square$$
@end tex


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Christopher Dimech
General Administrator - Naiad Informatics - GNU Project (Geocomputation)
- Geophysical Simulation
- Geological Subsurface Mapping
- Disaster Preparedness and Mitigation
- Natural Resource Exploration and Production
- Free Software Advocacy