In Vietnam literary & artistic treasure trove, the singing of CA TRU is a specific genre. It is a long standing folk music & singing and academic art - creation, at the same time. Hanoi is a one of some places that having a tales & legends narrating or mentioning as a cradle of the CA TRU. The book that you are holding is one of the most valuable & newest reference for researchers & the people who are interested in understanding & enjoying the singing of CA TRU. Contents: Chapters: I - Introduction. Explanations regarding some concepts & terminologies in singing of CA TRU. The Singing of CA TRU in the process of formation & development. The system & structure of CA TRU tunes / airs. Quantity. Names. Classification. Performing space. Historic distribution. CA TRU and its knowledge, concepts & perceptions. 2 - The words / lyrics of the CA TRU's tunes / airs ( the singings of CUA DINH, CHOI, THI, CHAU THI, CHAU CAM ) & related issues & problems. 3 - The singing of CA TRU of Hanoi and its practical life in history and at present. Legends in Lo Khe village & its relation / connection with CA TRU of Vietnam nationwide. The point of time of formation of the CA TRU through the CA TRU's song DAI NGHI BAT GIAP THUONG DAO GIAI VAN ( 15th century ). The List of 80 the most representative authors of CA TRU songs. Rebird of CA TRU. 4 - Appendix: Stone epitaphs. Material proof, historic evidence, relics & vestiges. Literary memoirs, notes & reportage mentioning the CA TRU