[3] [CITE[Pronunciation Lexicon Specification (PLS) Version 1.0]] ([TIME[2017-10-02 19:35:40 +09:00]]) <https://www.w3.org/TR/pronunciation-lexicon/>

[2] [CITE@en[音声認識文法の作成方法 — OpenHRI Manual]] ([TIME[2015-09-26 15:10:32 +09:00]]) <http://openhri.readthedocs.io/en/latest/workingwithgrammar-ja.html>

[1] [CITE@en[EPUB Content Documents 3.1]]
([TIME[2017-02-01 15:05:24 +09:00]])
<https://www.w3.org/Submission/2017/SUBM-epub-contentdocs-20170125/Overview.html#sec-pls-intro>