BibTeX supports storing constant strings using @String {key = value}. JabRef supports managing them using BibTeX → Edit strings, which opens the String Editor. These values can be used in fields. For example, you can have:

@String { kopp = "Kopp, Oliver" }
@String { kubovy = "Kubovy, Jan" }
@String { et = " and " }

and then in some entry for example

@Misc{m1,
  author = kopp # et # kubovy,
}

or

@Misc{m2,
  author = kopp # " and " # kubovy,
}

In the JabRef field editor, the author has to be inserted as #kopp# #et# #kubovy# or #kopp# and #kubovy#.

Rendering of constants in JabRef's entry editor

Strings are rendered specially in the entry editor. This is especially important in the case of months. For instance, take the following BibTeX entry:

@Misc{m3,
  month = may,
}

In JabRef, the entry editor then displays #may#. In case the entry editor just displays may, this is written as follows:

@Misc{m4,
  month = {may},
}

In other words: The character # indicates something special in the entry editor.

JabRef's typed Strings

JabRef enhances the concept of Strings to add a type to those @Strings. The issue is how to preserve such type of a string in a BibTeX file. JabRef adds the type though prefixes:

• @String { aKopp = "Kopp, Oliver" } is a @String with the type author.

• @String { iMIT = "{Massachusetts Institute of Technology ({MIT})}" } is a @String with the type of institution.

• @String { anct = "Anecdote" } is a @String of type other.

• @String { lTOSCA = "Topology and Orchestration Specification for Cloud Applications" } is a @String of type other.

Then @Strings of type author should be used for author and editors fields only. @Strings of type institution should be used for institution and organization fields only. @Strings of type publisher should be used only for publisher fields. And finally @Strings of type other can be used anywhere.

It can also happen that you will have the same institution for more types:

• @String { aMIT = "{Massachusetts Institute of Technology ({MIT})}" } if the institution will appear as author or editor

• @String { iMIT = "{Massachusetts Institute of Technology ({MIT})}" } if the institution will appear as institution or organization

• @String { pMIT = "{Massachusetts Institute of Technology ({MIT}) press}" } if the institution will appear as publisher.

Even if the last example may appear contradicting the intention was to remove duplicity and unify the names of persons and institutions.

Further reading

See https://tex.stackexchange.com/questions/303467/bibliography-contents-journal-names-not-abbreviated-even-with-ieeeabrv/303489#303489 for a MWE for string constants.