Just a note to remember substitution :
:%s/\ {http\(.*\)},/\ {\\url{http\1}},/
Goal was, in a bibtex file, to make an anchor with each url, using \url{} command.
For example,
@MISC{ademe,
title = {http://www.ademe.fr},
note = {L'Agence de l'environnement et de la ma\^itrise de l'\'energie},
}
became
@MISC{ademe,
title = {\url{http://www.ademe.fr}},
note = {L'Agence de l'environnement et de la ma\^itrise de l'\'energie},
}{jcomments on}