Dictionaries: Arabic-English, by Various. (1810-2009) Links to Google Books and Archive.org for online versions of many Arabic-English dictionaries.
Dictionaries: Persian-English, by Various. (1841-2003) Links to Google Books and Archive.org for online versions of Persian-English dictionaries.
Dictionary Used by the Guardian, by Universal House of Justice. (1997-12-08) Clarification/confirmation that the English dictionary used by Shoghi Effendi was Webster's (1934).