diff --git a/C4/Biblio.pm b/C4/Biblio.pm
index 04a6353f52..232d738b94 100644
--- a/C4/Biblio.pm
+++ b/C4/Biblio.pm
@@ -19,8 +19,7 @@ package C4::Biblio;
 # You should have received a copy of the GNU General Public License
 # along with Koha; if not, see <http://www.gnu.org/licenses>.
 
-use strict;
-use warnings;
+use Modern::Perl;
 use Carp;
 
 use Encode qw( decode is_utf8 );
diff --git a/C4/XSLT.pm b/C4/XSLT.pm
index c4fd6c292e..1d6edad751 100644
--- a/C4/XSLT.pm
+++ b/C4/XSLT.pm
@@ -8,21 +8,20 @@ package C4::XSLT;
 #
 # This file is part of Koha.
 #
-# Koha is free software; you can redistribute it and/or modify it under the
-# terms of the GNU General Public License as published by the Free Software
-# Foundation; either version 3 of the License, or (at your option) any later
-# version.
+# Koha is free software; you can redistribute it and/or modify it
+# under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
 #
-# Koha is distributed in the hope that it will be useful, but WITHOUT ANY
-# WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
-# A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
+# Koha is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
 #
-# You should have received a copy of the GNU General Public License along
-# with Koha; if not, write to the Free Software Foundation, Inc.,
-# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+# You should have received a copy of the GNU General Public License
+# along with Koha; if not, see <http://www.gnu.org/licenses>.
 
-use strict;
-use warnings;
+use Modern::Perl;
 
 use C4::Context;
 use C4::Branch;
diff --git a/opac/opac-ISBDdetail.pl b/opac/opac-ISBDdetail.pl
index 49d7ce7657..f325fd3586 100755
--- a/opac/opac-ISBDdetail.pl
+++ b/opac/opac-ISBDdetail.pl
@@ -39,8 +39,7 @@ the items attached to the biblio
 
 =cut
 
-use strict;
-use warnings;
+use Modern::Perl;
 
 use C4::Auth;
 use C4::Context;
diff --git a/opac/opac-showmarc.pl b/opac/opac-showmarc.pl
index 786693efe2..c3377277d8 100755
--- a/opac/opac-showmarc.pl
+++ b/opac/opac-showmarc.pl
@@ -4,21 +4,20 @@
 #
 # This file is part of Koha.
 #
-# Koha is free software; you can redistribute it and/or modify it under the
-# terms of the GNU General Public License as published by the Free Software
-# Foundation; either version 3 of the License, or (at your option) any later
-# version.
+# Koha is free software; you can redistribute it and/or modify it
+# under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
 #
-# Koha is distributed in the hope that it will be useful, but WITHOUT ANY
-# WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
-# A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
+# Koha is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
 #
-# You should have received a copy of the GNU General Public License along
-# with Koha; if not, write to the Free Software Foundation, Inc.,
-# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+# You should have received a copy of the GNU General Public License
+# along with Koha; if not, see <http://www.gnu.org/licenses>.
 
-use strict;
-use warnings;
+use Modern::Perl;
 
 # standard or CPAN modules used
 use CGI qw ( -utf8 );