Hi, I am am Swiss citizen living in Panama planning a trip to china (Tibet, shanghai, Beijing)

First, you need to prepare a set of application documents, including your passport, a photocopy of the passport's data page, the original and photocopy of your residence permit in Panama, a filled-out application form attached with a recently-taken color bare bareheaded photo, and round trip tickets and hotel reservations. Then submit the documents to the embassy there. Note that you had better not mention your intention to travel to Tibet. After entering China, you need to get a Tibet Travel Document from a local authorized travel agency. Otherwise, you may not book the train ticket or flight ticket to Tibet.

great many thanks for your answer and good to know that I can obtain the permit to travel to Tibet once I arrive to china. Went to Chinese embassy today and to obtain a visa here in Panama is very cumbersome. Not only they need 7 days but they also require a bank reference letter, bank statements and also an employment letter, all addressed to the Chinese embassy. Its easier to obtain it when I go to Switzerland for Christmas holidays, many thanks for your help!