In Chicago style, the first time that an item is cited, provide a full citation for the item. For subsequent citations, use a shortened version of the footnote, which includes:
1. John Bright, Jeremiah. The Anchor Bible (Garden City, NY: Doubleday, 1965), 60.
2. Danna Nolan Fewell and David M. Gunn, “Boaz, Pillar of Society: Measures of Worth in the Book of Ruth,” Journal for the Study of the Old Testament 45 (1989): 46.
1. Bright, Jeremiah, 60.
2. Fewell and Gunn, “Boaz, Pillar of Society,” 46.
The 17th edition of the Chicago Manual of Style discourages the use of ibid., which previously was used to refer the same source cited in the previous footnote.
Instead of using ibid., a shortened form of the citation may be used. The first time a shortened citation is used, all elements of short form should be included (author, brief title, page number). When citing the same source in multiple consecutive footnotes, to avoid repetition, the title may be omitted from the citation. The page number should be included in each footnote, even if it is the same as the previous footnote.
Full Citation: Danna Nolan Fewell and David M. Gunn, “Boaz, Pillar of Society: Measures of Worth in the Book of Ruth,” Journal for the Study of the Old Testament 45 (1989): 46.
Short Form: Fewell and Gunn, "Boaz, Pillar of Society," 46.
Shortest Form: Fewell and Gunn, 45.