MODS Individual Mappings for Other Related Item Cases

There is a case where relatedItem="host" being used by Emory for article’s parent journal title, a presentation’s parent conference proceedings title, etc. Even if you don't use relatedItem="host" for these cases, we still would like to map these general concepts to something. Essentially how does one represent these relationships? A further example of this question can be found in: https://docs.google.com/document/d/1eyg_jqtJUVYbaHpxjE4s2BUci0HhvwT9CP3wme-ja1I/edit

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