pid_to_issn


git-svn-id: svn://oss.dbc.dk/sync_php/php/OpenLibrary/OpenOrder/trunk@56140 30e9dc4a-7611-4fbc-83ba-eecf79b76bd0
remove "


git-svn-id: svn://oss.dbc.dk/sync_php/php/OpenLibrary/OpenOrder/trunk@56146 30e9dc4a-7611-4fbc-83ba-eecf79b76bd0
normalize_issn()


git-svn-id: svn://oss.dbc.dk/sync_php/php/OpenLibrary/OpenOrder/trunk@56151 30e9dc4a-7611-4fbc-83ba-eecf79b76bd0