my @ids = map {
       s/<.+?>//gr
    =~ s/^(\d+([stnrdh]{2}|))/NUMWORDS($1)/er
    =~ s/(.)\.\w{2,5}?$/$1/r
    =~ s/&amp/and/gr
    =~ s/&/and/gr
    =~ s/Æ/Ae/gr
    =~ s/Ç/C/gr
    =~ s/Ü/U/gr
    =~ s/(è|é|ê)/e/gr
    =~ s/#/No/gr
    =~ s/ /_/gr
    =~ s/[^\w:.\-]//gr
  } grep { defined } @base;