Add license

bibget.pl

@@ -1,4 +1,21 @@
 #!/usr/bin/perl
+#
+# Extract used the bibliography elements into a single file
+#
+# Copyright 2005-2016 Diomidis Spinellis
+#
+#   Licensed under the Apache License, Version 2.0 (the "License");
+#   you may not use this file except in compliance with the License.
+#   You may obtain a copy of the License at
+#
+#       http://www.apache.org/licenses/LICENSE-2.0
+#
+#   Unless required by applicable law or agreed to in writing, software
+#   distributed under the License is distributed on an "AS IS" BASIS,
+#   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#   See the License for the specific language governing permissions and
+#   limitations under the License.
+#
 
 sub getcitation {
 	my($fname) = @_;