Dehghan Nezhad A.
Ukr. Mat. Zh. - 2010. - 62, № 4. - pp. 567–571
The purpose of this paper is to introduce and discuss the concepts of G-best approximation and $a_0$ -orthogonality in the theory of $G$-metric spaces. We consider the relationship between these concepts and the dual $X$ and obtain some results on subsets of $G$-metric spaces similar to normed spaces.