An example of Riemannian manifolds satisfying $R(X,\,Y)\cdot R=0$ but not $\nabla R=0$
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چکیده
منابع مشابه
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ژورنال
عنوان ژورنال: Tohoku Mathematical Journal
سال: 1972
ISSN: 0040-8735
DOI: 10.2748/tmj/1178241595