Mirza Mahmud's Diary

"The Universal House of Justice, in a letter of April 30, 1984 to the National Spiritual Assembly of the Bahá'ís of the United States, stated that it . . . attaches great importance to this work which, as you may know, is regarded as a reliable account of `Abdu'l-Bahá's travels in the West and an authentic record of His utterances, whether in the form of formal talks, table talks or random oral statements. Mírzá Mahmúd was a careful and faithful chronicler and engaged in assembling and publishing his work with the permission of the beloved Master, as he states in the Introduction. Indeed, Shoghi Effendi drew upon it for details about the Master's visit to the West in writing God Passes By . . ."

http://bahai-library.com/books/mahmud/