Why there is no DOI field for journal articles?
Journal articles usually have their own DOI (for example: http://www.plosone.org/article/Authors/info:doi/10.1371/journal.pone.0059110), but there is no such field for "Journal article" item. Because of this journal articles, when added by DOI in Zotero, become articles from periodic series. For my mind, it is not right.
And it is an article from journal withot such field: https://fotki.yandex.ru/next/users/a-morkovin/album/975/view/569051
Maybe I miss something important...
But still I don't understand what is the function of fields "Series", "Series name", "Series text". This fields remain blank when I import an article from a scientific journal. They are needed for book series like "BTO Guide", not for journals.