I have an external HTML file I\'d like to have linked form either my doxygen \"Related Pages\" tab or the left hand frame. It seems I need to use the \\link com
\\link
We have a Markdown support in doxygen nowadays. Your code may be a clearer:
/*! \mainpage MY TITLE HERE * \anchor intro_sec * # External resources * [My external page](http://link_to_my_external_page.html) */
The above should render somewhat close to:
My external page