The only content of this section in https://doxygen.github.io/doxygen-docs/index.html#autotoc_md6 is "To do."

I think this is an important omission, as newcomers wanting to add new and exotic output formats won't know the parsing/output process.

For anyone aspiring to write this section, where should they look in the source code and/or other documentation to understand the output process. Which source/header files are good examples of an output module that works correctly on which others can base their output files?