New Schaff-Herzog Encyclopedia of Religious Knowledge: Catholic Apostolic Church
- Three-page article on the history and doctrine of this church. Includes bibliography. Scanner errors make HTML version difficult to read in spots; page images are available in PNG format.
- http://www.ccel.org/ccel/schaff/encyc02/Page_457.html

The Eclipse of the Hope
- The ninth chapter of Iain H. Murray's "The Puritan Hope." Has a great deal of information on the character and teachings of Edward Irving, so influential in later interpretations of prophecy.
- http://www.revival-library.org/catalogues/puritan/murrayi-puritanhope/09.htm

New Apostolic Church International
- Window to the Apostolic faith in Europe and beyond.
- http://www.nak.org/

Australia District of the New Apostolic Church
- Part of New Apostolic Church International. The District covers Australia, New Zealand, part of Papua New Guinea, and several countries in the South Pacific. Map, contacts, congregations, areas of missionary work.
- http://www.newapostolic.org.au/

New Apostolic Church Philippines
- Part of New Apostolic Church International, served by Canadian missionaries. Has over 1000 local churches. Introduction to the work in the Philippines, how to get in contact, photo gallery, summary of beliefs.
- http://www.nac-philippines.org/

New Apostolic Church of North America
- Present in Canada, the United States, Mexico, and Puerto Rico. Bible study, church locator, news, information, and features for every age group. In English, French, and Spanish. May not work in some browsers.
- http://newapostolicchurch.org/

Doctrine of the New Apostolic Church
- Overview of the beliefs of this church from an outside source.
- http://www.naki.de/_nak_eng/nak_lehre_e.htm

United Apostolic Church Europe
- Apostolic communities throughout Europe and internationally. Site in English, German, and Dutch.
- http://www.united-apostolic.org/

Restored Apostolic Mission Church, Tribe Juda
- Introduction to the Apostolic work in the Netherlands. Site in English, German, and Dutch. May not work in some browsers.
- http://www.hazk.nl/index_uk.html

Irving, Edward
- Brief biographical entry, in the Columbia Encyclopedia, 6th ed.
- http://www.bartleby.com/65/ir/Irving-E.html

Columbia Encyclopedia: Catholic Apostolic Church
- Brief entry. Mentions the New Apostolic Church as well.
- http://www.bartleby.com/65/ca/CatholicAC.html

Apostolic Church of Queensland
- Official site of this church body. From the Germanic/Prussian wing of the Catholic Apostolic renewal. History, explanation of their emblem, coming events, church addresses. "Book of Faith" explains beliefs.
- http://www.apostolicchurchqld.org.au/default.htm