Wikipedia:Manual of Style/Bahá'í spelling

Baháʼí spelling is used for expressions and names if all four of following conditions are met:
 * 1) The expression or name is found with that spelling in the glossary at the bahai.org website, currently https://news.bahai.org/media-information/style-guide/ – or whatever updated digital version of that guide, if it uses unicode characters and is accepted as such by consensus
 * 2) The spelling is not explicitly forbidden by the WP:AT policy
 * 3) The expression or name is only, or nearly only, used in connection with Baháʼí Faith (i.e. it has no common or widespread usage outside that Faith)
 * 4) Single quotation marks (e.g. ’) and curly apostrophes (e.g. ’) are routinely converted to the straight (simple) apostrophe character (') per general WP:MOS recommendations.

Note that various Baháʼí words and proper names, such as Baháʼí Faith, Baháʼu'lláh and Ḍíyáʼu'lláh, are properly written with a modifier letter apostrophe after the letter a, as defined by the glossary in the 1st condition, and used primarily for glottal sounds; thus, this glottal ʼ does not meet the 4th condition's single quotation marks nor curly apostrophes requirement.

For usage of the expression or name as (or: in) an article title there is a fifth condition:
 * 1) redirects from all common simpler and/or more complex variant spellings of the expression or name should be existing

Examples:
 * "children's classes", not "children’s classes" (found in glossary, but fails 3rd and 4th conditions).
 * The routine conversion mentioned in the 4th condition only applies to single quotation marks and curly apostrophes, thus:
 * and not:
 * Qur'án and Kitáb-i Íqán are quoted as in the title of the journal article, not adapted to the spelling of Wikipedia's article titles (Quran and Kitáb-i-Íqán respectively), per MOS:PMC.
 * Qur'án and Kitáb-i Íqán are quoted as in the title of the journal article, not adapted to the spelling of Wikipedia's article titles (Quran and Kitáb-i-Íqán respectively), per MOS:PMC.
 * Qur'án and Kitáb-i Íqán are quoted as in the title of the journal article, not adapted to the spelling of Wikipedia's article titles (Quran and Kitáb-i-Íqán respectively), per MOS:PMC.