Can I use $ref in examples?

Replace "example" with "examples" (plural) as shown below:

'200':
  description: The request is successful
  content:
     application/json:
         schema:
            $ref: '#/components/schemas/ResponseSchema'
         examples:      # <------
            example1:   # <------ arbitrary name
               $ref: '#/components/examples/200Example'

...
components:
  examples:
    200Example:
      summary: A short summary of this example
      value:
        key1: value1
        key2: value2