Btukfyl

   documentclass[a4paper,12pt]{report}

  %------------------------------------------------------------

  usepackage{amssymb,amsmath,amsthm,latexsym,mathrsfs,amsfonts,dsfont}

  %-----accent                      

 usepackage[utf8]{inputenc}

usepackage[T1]{fontenc}

usepackage{xcolor}

usepackage[colorlinks=true,pagebackref=true]{hyperref}

 hypersetup{urlcolor=blue, citecolor=red, linkcolor=blue}

  newtheorem{corollary}{Corollary}[section]



usepackage[capitalise,noabbrev,nameinlink]{cleveref}

begin{document}

chapter{Preliminary}

 ....The crucial idea of the proof is to make use ..... (see cref{fekete} in cref{app}). 



chapter*{Appendix}label{app}

begin{corollary}label{fekete}



end{corollary}

end{document}

   documentclass[a4paper,12pt]{report}

  %------------------------------------------------------------

  usepackage{amssymb,amsmath,amsthm,latexsym,mathrsfs,amsfonts,dsfont}

  %-----accent                      

 usepackage[utf8]{inputenc}

usepackage[T1]{fontenc}

usepackage{xcolor}

usepackage[colorlinks=true,pagebackref=true]{hyperref}

 hypersetup{urlcolor=blue, citecolor=red, linkcolor=blue}

  newtheorem{corollary}{Corollary}[section]



usepackage[capitalise,noabbrev,nameinlink]{cleveref}

begin{document}

chapter{Preliminary}

 ....The crucial idea of the proof is to make use ..... (see cref{fekete} in cref{app}). 



chapter*{Appendix}label{app}

begin{corollary}label{fekete}



end{corollary}

end{document}

   documentclass[a4paper,12pt]{report}

  %------------------------------------------------------------

  usepackage{amssymb,amsmath,amsthm,latexsym,mathrsfs,amsfonts,dsfont}

  %-----accent                      

 usepackage[utf8]{inputenc}

usepackage[T1]{fontenc}

usepackage{xcolor}

usepackage[colorlinks=true,pagebackref=true]{hyperref}

 hypersetup{urlcolor=blue, citecolor=red, linkcolor=blue}

  newtheorem{corollary}{Corollary}[section]



usepackage[capitalise,noabbrev,nameinlink]{cleveref}

begin{document}

chapter{Preliminary}

 ....The crucial idea of the proof is to make use ..... (see cref{fekete} in cref{app}). 



chapter*{Appendix}label{app}

begin{corollary}label{fekete}



end{corollary}

end{document}

   documentclass[a4paper,12pt]{report}

  %------------------------------------------------------------

  usepackage{amssymb,amsmath,amsthm,latexsym,mathrsfs,amsfonts,dsfont}

  %-----accent                      

 usepackage[utf8]{inputenc}

usepackage[T1]{fontenc}

usepackage{xcolor}

usepackage[colorlinks=true,pagebackref=true]{hyperref}

 hypersetup{urlcolor=blue, citecolor=red, linkcolor=blue}

  newtheorem{corollary}{Corollary}[section]



usepackage[capitalise,noabbrev,nameinlink]{cleveref}

begin{document}

chapter{Preliminary}

 ....The crucial idea of the proof is to make use ..... (see cref{fekete} in cref{app}). 



chapter*{Appendix}label{app}

begin{corollary}label{fekete}



end{corollary}

end{document}

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