/lɛtər ʌv rɪˈkwɛst/ – Phrase
Definition: Yêu cầu bằng văn bản.
A more thorough explanation: 1. (also: request letter) a letter asking someone for something
2. an official letter for judicial help sent by a court to a court in another jurisdiction
Example: 1. The body of the very simplest letter of request is usually only one or two paragraphs.
2. Under the first paragraph of Article 4, the Letter of Request shall be in the language of the authority requested to execute it.