Edited by J. Deretz and A. Nocent.
London: Geoffrey Chapman, 1968.
For print version locations, see the UofT Library Catalogue.
Paragraph-length excerpts arranged alphabetically by topic. The English edition is a slightly abridged version of the French original, Synopse des textes conciliaires. There is also a German translation, Konkordanz der Konzils Texte.
The online version is available on the Internet Archive, a trusted source, but one for which it is necessary to create a free account and login.