This will serve as a proof.

以此为凭。

《新英汉大辞典》

Postmark serves as a proof.

邮戳为凭。

《新英汉大辞典》

A digital signature stamps a proof of origin authenticity.

数字签名标志原始的真实性的验证。

youdao

Professor Yoshino explains. "Shakespeare calls this a problem of ocular proof, the idea that we need to see evidence before we believe in it -- and that,oftentimes, when metaphysical questions of guilt or innocence are difficult for us to answer, we have a tendency to reduce them to questions that pertain to physical evidence.

VOA: special.2011.06.06

He says Poland is now ready to be a responsible co-leader in Europe, and this signature is proof of that.

VOA: standard.2009.10.10

They look like an extra-large version of the World War Two jeep, but enclosed, with small blast-proof windows, a protected machine gun position on top and a variety of high-tech gear inside and out.

VOA: standard.2009.11.02

It will be no small victory for Republicans to deny Democrats a filibuster-proof 60-seat supermajority or even a working one of 58 seats if you add Arlen Specter and Susan Collins to the Dem caucus.

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Final vote on the bill was 286-129, a veto-proof majority.

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Democrats in the Senate are hoping to win 60 seats -- enough to secure a filibuster-proof majority in the Senate.

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