Written authorisation must be provided by the client for any changes to the original work specification or for any additional work.

客户对原先工作（设计）有 任何修订或是有另外额外的工作时， 必须提供书面确认。

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Wal-Mart says it had subcontracted the work to the Tazreen factory without authorisation.

BBC: Bangladesh textile workers' deaths 'avoidable'

We signed an authorisation to proceed yesterday with TAS to immediately begin work designing and building our satellites, and this puts us on track for our first launch of the new satellites in the first quarter of 2015.

BBC: Huge order for Iridium spacecraft