Basically, if I am to cite a book chapter in a collected volume, it gets a full citation. But if I cite another chapter in the same book, the citation to the second item would be truncated, using a shortened title for the edited book, just the last names of the editors, and no publishing information. Here is a screenshot from the SBL Handbook with the issue highlighted:
In Jon's words from our correspondence: "You want it [metatypes] to never work for the first citation but only subsequent citations of chapters [children] from the book [parent]".
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