updated link, validated

Author: KingdomOfEnds

articles/digital-twins/concepts-device-ingress.md

@@ -66,7 +66,7 @@ You can customize your device's message format and payload to fit your solution'
 |---|---|---|---|
 | **DigitalTwins-Telemetry** | 1.0 | Yes | A constant value that identifies a message to the system. |
 | **DigitalTwins-SensorHardwareId** | `string(72)` | Yes | A unique identifier of the sensor that sends the **Message**. This value must match an object's **HardwareId** property for the system to process it. For example, `00FF0643BE88-CO2`. |
-| **CreationTimeUtc** | `string` | No | An [ISO 8601](https://en.wikipedia.org/wiki/ISO_8601) formatted date string that identifies the sampling time of the payload. For example, `2018-09-20T07:35:00.8587882-07:00`. |
+| **CreationTimeUtc** | `string` | No | An [ISO 8601](https://www.iso.org/iso-8601-date-and-time-format.html) formatted date string that identifies the sampling time of the payload. For example, `2018-09-20T07:35:00.8587882-07:00`. |
 | **CorrelationId** | `string` | No | A UUID that's used to trace events across the system. For example, `cec16751-ab27-405d-8fe6-c68e1412ce1f`.
 
 ### Send your message to Digital Twins