BibTeX:
@incollection{JulietThompson1947,
  author = {Juliet Thompson},
  title = {The Mathematician at the Window},
  booktitle = {The Diary of Juliet Thompson},
  year = {1947},
}

APA:
Juliet Thompson. (1947). The Mathematician at the Window. In *The Diary of Juliet Thompson*.

MLA:
Juliet Thompson. "The Mathematician at the Window." *The Diary of Juliet Thompson*, 1947.

Chicago:
Juliet Thompson. "The Mathematician at the Window." In *The Diary of Juliet Thompson*, 1947.