function canonical_ISSN in ISBN Field 6

1 call to canonical_ISSN()

canonical_ISN in ./isbn.inc

File

./isbn.inc, line 374

Code

function canonical_ISSN($issn_proto) {
  $issn_proto = ISN_clean($issn_proto);
  return substr($issn_proto, 0, 4) . "-" . substr($issn_proto, 4, 4);
}