+ ((eq format 'latex) (format "\\eqref{%s}" keyword))
+ ;;considering the fact that latex's the standard of math formulas, just use mathjax to render the html
+ ;;customize the variable 'org-html-mathjax-template' and 'org-html-mathjax-options' refering to 'autonumber'
+ ((eq format 'html) (format "\\eqref{%s}" keyword)))))