Message
Article with article-type "correction", "retraction", or "expression-of-concern" (@article-type) must have <ali:free_to_read/> or a have license-type="open-access"
Rule XPath:
This rule ASSERTS the following, raising an alert if FALSE:
if (@article-type = ('correction', 'retraction', 'expression-of-concern')) then exists(front/article-meta/permissions/ali:free_to_read
| front/article-meta/permissions/license[@license-type = 'open-access']) else true()