The occupant is not required to furnish facilities for postal service, but may take charge of them itself, especially if the officials of the occupied district fail to act or to obey its orders.

占领者无须建立邮递服务，但亦得全盘自行控制，特别是在占领区域有关当局无法或不愿意执行或遵循占领者命令时。

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Prior to the Postal Act of 1863, intercity letters were either held at the destination post office for pick-up or delivered by an independent contractor.

FORBES: Toward A Solvent U.S. Postal System

The European Postal Services Act reserves letters of less than 100g for national mail operators but this restriction will be lifted in 2007.

ECONOMIST: Royal Mail

Its name is PAEA, or The Postal Accountability and Enhancement Act passed by Congress, coincidentally enough, in 2006.

FORBES: Going Postal: How Congress Has Failed Its Shareholders