```
% pandoc --citeproc -t plain
---
references:
- id: smith
  author: John Smith
  issued: 2019
  title: Insects
  type: book
...

@smith [chap. 6]

@smith [chapter 6]

@smith [Chap. 6]

@smith [Chapter 6]
^D
John Smith (2019, chap. 6)

John Smith (2019, chap. 6)

John Smith (2019, chap. 6)

John Smith (2019, chap. 6)

John Smith. 2019. Insects.
```