theme_biblio_tabular() throws notices due to change in input format handling

# Notice: Undefined property: stdClass::$format in theme_biblio_tabular() (line 253 of sites/all/modules/biblio/includes/biblio_theme.inc).

The ideal way to fix this would be to migrate to a proper text field (like node body is in D7). A quick work around is to apply a check_plain() or a filter_xss() with a safe set of tags.