Treaties and Conventions Relating to Tibet
Chefoo Convention (1876) 
Between The British Government and the Government of China (Extract)
Her Majesty's Government having it in contemplation to send a mission of exploration next year, by way of Peking, through Kansuh and Koknor, or by way of Szechuan to Thibet, and thence to India, the Tsungli Yamen, having due regard to the circumstances, will, when the time arrives, issue the necessary passports, and will address letters to the High Provincial Authorities and the Residents in Thibet. If the Mission should not be sent by these routes but should be proceeding across the Indian frontier to Thibet, the Tsungli Yamen, on receipt of a communication to that effect from the British Minister, will write to the Chinese Resident in Thibet, and the Resident, with due regard to the circumstances, will send officers to take care of the Mission, and passports for the Mission will be issued by the Tsungli Yamen, that its passage be not obstructed.
1. Source: H.E. Richardson, A Short History of Tibet (New York, 1962), p. 249. The above is a separate article. The main body of the Convention did not concern Tibet.
Reproduced from M. C. van Walt van Praag's Status of Tibet: History, Rights and Prospects in International Law. With permission of the author.