The other answers are correct, but let me offer a different angle.
Stop thinking, and start using the Bibtex entries from Zbmath; in this case, click on the Bibtex button before the references on https://zbmath.org/7576459 . Life is too short to worry about references and insert them by hand.
EDIT: Note that this piece of advice is specific for mathematics. Bibtex entries offered by most generalist sites, such as the publishers' sites and Google Scholar, often have poor quality and get capitals and diacritics wrong. However, for mathematics, there are two literature databases that produce very high-quality Bibtex entries that can be used without double-checking them: Zbmath (100% free, offered by the European Mathematical Society), and Mathscinet (good if your university is a subscriber but severely limited in its free version, by the American Mathematical Society).