"Forms of Address". Garza Protocol Associates (dalam bahasa Inggris). 22 March 2017. Diakses tanggal 9 June 2021.
un.int
"Protocol and Liaison Service"(PDF). 24 August 2016. Diakses tanggal 9 June 2021.Parameter |url-status= yang tidak diketahui akan diabaikan (bantuan)
usaprotocol.com
Protocol - The Complete Handbook of Diplomatic, Official, and Social Usage (page 21), by Mary Jane McCaffree and Pauline Innes, published by Hepburn Books, Dallas, Texas [1]Diarsipkan 1 March 2012 di Wayback Machine., 1977, 1985, 1989, 1997 ISBN0-941402-04-5
web.archive.org
Protocol - The Complete Handbook of Diplomatic, Official, and Social Usage (page 21), by Mary Jane McCaffree and Pauline Innes, published by Hepburn Books, Dallas, Texas [1]Diarsipkan 1 March 2012 di Wayback Machine., 1977, 1985, 1989, 1997 ISBN0-941402-04-5
