Originally posted at bahaistudy.org, archived at archive.org, which notes "Talks by Mr. & Mrs. Robarts, Mr. & Mrs. Khadem, and Mrs. Banani in 1984." These are presumably John and Audrey Robarts, Zikrullah Khadem, and Musa Banani, but I am not sure. No information is given about the context of this talk, but it is likely the proceedings later published as The Vision of Shoghi Effendi.