Standardize bib references and Examples subsection in docstrings.

Standardize bib references and Examples subsection in docstrings.

Recipe:

+ Write a #### Examples subsection below Args/Returns/Raises to illustrate examples. If the docstring's last line is a ``` closing a code snippet, add an empty line before closing the docstring with """. This properly displays the code snippet.

+ Write a #### References subsection at the bottom of any docstring with citations. Enumerate all references in alphabetical order. Individual bibentries use ICLR?s bibliography style, which borrows from icml2010.bst and which itself borrows from plainnl.bst. Add a link to the paper if the publication is open source (ideally, arXiv).

PiperOrigin-RevId: 189670932