Consider the generated citation for DOI 10.1007/bf02276805:
{{cite journal | last=Schütte | first=Kurt | title=Einführung der Normalfunktionen$upTheta$ a ohne Auswahlaxiom und ohne Regularitätsbedingungohne Auswahlaxiom und ohne Regularitätsbedingung | journal=Archiv für Mathematische Logik und Grundlagenforschung | publisher=Springer Nature | volume=17 | issue=3-4 | year=1975 | pages=171–178 | url=https://doi.org/10.1007%2Fbf02276805 | doi=10.1007/bf02276805 | ref=harv | accessdate=May 21, 2017}}
There's no reason to include a url field when a doi field is included. (This might hold for other IDs also, but I'm not sure about those.) Note however that the citation is rendered differently on Wikipedia depending on whether a url field is included or not (the title is linked vs. not linked).
Consider the generated citation for DOI 10.1007/bf02276805:
There's no reason to include a url field when a doi field is included. (This might hold for other IDs also, but I'm not sure about those.) Note however that the citation is rendered differently on Wikipedia depending on whether a url field is included or not (the title is linked vs. not linked).