Title of the journal series (bibliographic meaning) or the title of a series of articles internal to one issue of a journal. This is an NLM not an APA element.
(#PCDATA | ext-link | related-article | inline-supplementary-material | bold | italic | monospace | overline | roman | sans-serif | sc | strike | underline | alternatives | inline-graphic | mml:math | fn | target | xref | sub | sup)*
Any combination of:
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