When citing an individual letter in the edition, it is important to include the unique 4-digit identifying number of the letter.
Cather, Willa. “#2077: Willa Cather to Roscoe Cather, June 23 [1917].” The Complete Letters of Willa Cather, edited by the Willa Cather Archive team, The Willa Cather Archive, 2018, cather.unl.edu. Accessed 23 Jan. 2018.
Cather, Willa. 2018. “#2077: Willa Cather to Roscoe Cather, June 23 [1917].” In The Complete Letters of Willa Cather, edited by the Willa Cather Archive team. The Willa Cather Archive. Accessed January 23, 2018. https://cather.unl.edu/writings/letters/let2077.
If multiple letters are referenced, cite The Complete Letters of Willa Cather in the bibliography; do not cite each letter individually.
The Willa Cather Archive team, eds. The Complete letters of Willa Cather. The Willa Cather Archive. Accessed January 23, 2018. https://cather.unl.edu/writings/letters.
Cather, Willa. “#2077: Willa Cather to Roscoe Cather, June 23 [1917].” In The Complete Letters of Willa Cather, edited by the Willa Cather Archive team. The Willa Cather Archive, 2018. Accessed January 23, 2018. https://cather.unl.edu/writings/letters/let2077.
If multiple letters are referenced, cite The Complete Letters of Willa Cather in the bibliography; do not cite each letter individually.
The Willa Cather Archive team, eds. The Complete letters of Willa Cather. The Willa Cather Archive. Accessed January 23, 2018. https://cather.unl.edu/writings/letters.