Need option to link Periodical part to larger periodical

[hudajkhan]

Cataloging workflow: In public display of a Periodical part, "is part of" does not appear as an option to link it to the larger periodical. In the control panel, "is part of" appears as an option under Add new statement/Predicate but has no object class. The workaround I've found is to temporarily remove type Periodical part in the control panel, go back to public display where "is part of" now appears and link to the larger periodical, then go back to the control panel and restore type Periodical part.

Reported by Robert Rendall/Columbia