NSperformanceManagement.yaml

        503:
          $ref: "responses/SOL005_resp.yaml#/responses/503" 
    get:
      summary: Notification endpoint.
      description: >
        The GET method allows the server to test the notification endpoint that is provided by the client, 
        e.g. during subscription.
      parameters:
        - name: Accept
          description: >
            Content-Types that are acceptable for the response.
            Reference: IETF RFC 7231
          in: header
          required: true
          type: string
        - name: Authorization
          description: >
            The authorization token for the request.
            Reference: IETF RFC 7235
          in: header
          required: false
          type: string
      responses:
        204:
          description: >
            The notification endpoint was tested successfully.
            The response body shall be empty. 
        400:
          $ref: "responses/SOL005_resp.yaml#/responses/400"
        401:
          $ref: "responses/SOL005_resp.yaml#/responses/401"
        403:
          $ref: "responses/SOL005_resp.yaml#/responses/403"                        
        500:
          $ref: "responses/SOL005_resp.yaml#/responses/500"
        503:
          $ref: "responses/SOL005_resp.yaml#/responses/503"