Vols. for 1979-<1986> distributed in the U.S. and Canada exclusively by Gale Research Co., Detroit, Mich. (Gale Research Co. presented on t.p. in v. for 1979-1983 as publisher).
Vols. for <1994> published by: Cartermill; for <1996>- by Keesing's Worldwide.
Vol. for 2009 called also 250th anniversary ed., and accompanied by special ed. facsimile reprint of the 1758 first issue.
Published: London : Cartermill, 1994-1995; London : Keesing's Worldwide, 1996-<2004>; Bethesda, MD : ProQuest ; Cambridge, UK : The Quorum, <2008->
Issues for 1964-1978 published in London and New York editions, 1979- in London edition only.
Latest issue consulted: 258th ed. (2017).