I use UTF-8 encoding to type a document in French, with the following definitions for guillemets:

\DeclareUnicodeCharacter{AB}{\og}
\DeclareUnicodeCharacter{BB}{\fg\xspace}


and the Babel package:

\usepackage[francais]{babel}


However, when I type a text like ceci cela «~quoted~» ceci cela, the spacing is wrong around the opening guillemet:



Notice that the space before the opening guillemet is too small, and the spacing after is too large. The closing guillemet has correct spacing. How could I fix that?


Question: what is exactly the difference between the Selberg class and the set of Artin L-functions?
Answer: As far as I know, the precise conjecture for what you are asking is:


  All the elements of the Selberg class that are not Artin L-functions
  are:
  
  
  motivic L-functions of dimension bigger than 0.
  transcendental L-functions
  


Note that Artin L-functions are the 0-dimensional motivic L-functions.

Also, transcendental L-function is an umbrella term for automorphic L-functions that are not motivic.