Narang T. D.
Common fixed points and invariant approximation of $R$-subweakly commuting maps in convex metric spaces
Ukr. Mat. Zh. - 2010. - 62, № 10. - pp. 1367–1376
Sufficient conditions for the existence of a common fixed point of $R$-subweakly commuting mappings are established within the framework of a convex metric space. As applications, we obtain various results on the best approximation for this class of mappings generalizing the results known from the literature.