"Three single tickets and one letter" are:

1. "Three single tickets": reception approval form, reception list and reception menu. All receptions must be truthfully filled out by the reception manager, indicating the name, unit, position, number of visitors, the purpose of the visit and the number of days of activities, which should be signed by the office and manager, and the object and time of reception should be indicated when signing the receipt.

2. "One vote": official catering invoice. As a proof of financial reimbursement.

3. "One letter": official letter from the sending unit. If it is really necessary to receive a business trip, the sending unit shall send an official letter to the receiving unit to inform the content, itinerary and personnel.

Extended information:

On February 8, 2113, the People's Republic of China * * and the Central People's Government website published the "Regulations on the Administration of Domestic Official Reception of Party and Government Organs" issued by the General Office of the Central Committee and the General Office of the State Council.

the regulations require the reception object to dine by itself according to the prescribed standards (i.e. food standards for travel, meetings, training, etc.), and shall not be passed on to the reception unit. Due to the need of work, the reception unit can only arrange a working meal once. The number of people accompanying meals is strictly controlled. If the reception object is less than ten people, the number of people accompanying meals shall not exceed three; More than ten people, shall not exceed 1/3 of the number of reception objects.

The Regulations impose strict restrictions on the dining place and consumption content of working meals: home-cooked meals should be provided for working meals; Do not provide high-end dishes such as shark's fin and bird's nest and dishes made with wild protected animals, do not provide cigarettes and high-end drinks, and do not use private clubs and high-consumption dining places.

Reference: Baidu Encyclopedia-Provisions on the Administration of Domestic Official Reception of Party and Government Organs