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“ Foreign words in a Persian context, including Arabic words, are romanized according to the rules for Persian. For short vowels not indicated in the script, the Persian vowels nearest the original pronunciation of the word are supplied in romanization. 14. Dictionaries. In romanizing Persian, the Library of Congress has found it necessary to consult dictionaries as an appendage to the romanization tables, primarily for the purpose of supplying vowels. ”

“ Ghulām ʻAlī غلامعلی or غلام علی Shāh Jahān شاهجهان or شاه جهان Ibn Abī Ṭālib ابن ابیطالب or ابن ابي طالب Orthography of Persian in Romanization
11. Capitalization. (a) Rules for the capitalization of English are followed, except that the Arabic article al is lowercased in all positions. (b) Diacritics are used with both capital and lowercase letters. 12. The single prime ( ʹ ) is used: (a) To separate two letters representing two distinct consonantal sounds, when the combination might otherwise be read as a digraph. ”