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\begin{document}
	
	jjkkjhjkkjlkjlkj lkjlkjlj 
	
	\begin{theorem}[\cite[page 130]{6}]
		IFF j oi oooi 
	\end{theorem}
	
	
	
	
	
	
	
	
	
	\begin{thebibliography}{99}
		
		\bibitem{6}
		Belluce, L.P. ; Kirk, W.A. ; Nonexpansive in Banach spaces;
		Illinois J. Math. 11 1967 474–479. 
		
		
		
		
	\end{thebibliography}
\end{document}