As many different kinds of materials (e.g., letters, books, pamphlets, newspaper articles, photographs, journal entries, speeches) can be used as primary sources, the structure of citations for primary sources published in edited collections can vary significantly. Generally, the structure of the first part of the citation reflects the kind of primary source being cited, while the latter part references the edited collection and is similar in structure to citations for chapters in an edited work (see, for instance, this example).
Example 1 – Book-length Work in an Edited Collection
N: 1. Ken Mcneilly, The Common Ground, in ReView: An Anthology of Plays Committed to Social Justice, ed. Julia Gray (Rotterdam: Sense Publishers, 2017), 62.
B: McNeilly, Ken. The Common Ground. In ReView: An Anthology of Plays Committed to Social Justice,
edited by Julia Gray. Rotterdam: Sense Publishers, 2017.
Example 2 – Shorter Work in an Edited Collection
N: 1. Frederick Edward Maning, "The Dying Maori Chief and his Old and Young Wives," in The Ethics of Suicide: Historical Sources, ed. Margaret Pabst Battin (Oxford: Oxford University Press, 2015), 540.
B: Maning, Frederick Edward. "The Dying Maori Chief and his Old and Young Wives." In The Ethics of
Suicide: Historical Sources, edited by Margaret Pabst Battin, 539-40. Oxford: Oxford University
Press, 2015.
NOTE: Quotation marks are used for the titles of articles, poems, speeches, sermons, and the like. For more information on italics versus quotation marks for titles of cited works, see The Chicago Manual of Style, 14.86.
Example 3 – Letter in an Edited Collection
N: 1. George Orwell to T. S. Eliot, June 28, 1944, in A Life in Letters, ed. Peter Davison (London: Harvill Secker, 2010), 236.
B: Orwell, George. George Orwell to T. S. Eliot, June 28, 1944. In A Life in Letters, edited by
Peter Davison, 236. London: Harvill Secker, 2010.
NOTE: You may also cite the whole edited collection, rather than a single letter, in your bibliography:
B: Orwell, George. A Life in Letters. Edited by Peter Davison. London: Harvill Secker, 2010.