9.4 Additionally, the general terms and conditions of delivery or purchase of the Seller shall apply. Any amendment to this Agreement and any notice or other communication under or in connection with this Agreement shall only be effective if made in writing. The sender may in any event only rely on a communication if it actually reaches the recipient. If the delivery of a communication that has been sent by registered mail or through a reputable international courier service is delayed, the communication shall be deemed to have reached the addressee at such time when it would under normal circumstances have been delivered to it.