Place(address, otherInfo)	Register all addresses.
Perform(songID, ssn)	Register which songs are performed by which musicians
AlbumProducer(ssn, albumIdentifier, copyrightDate, speed, title)	Registers albums and their producers (who are musicians).
Musicians(ssn, name, annualIncome)	Registers the ssn of musicians and their names and annual incomes
Instruments(instrID, iname, key)	Registers instruments
Plays(ssn, instrID)	Registers which musicians play which instruments
SongsAppears(songID, authorSSN, title, albumIdentifier)	Registers songs and which albums they appear. Every song must have exactly one author who is a musician, and appears in exactly one album.
Lives(ssn, address, phone)	Registers where musicians live and which phones they use.

Use SQL to express the following query: Find the musicians who perform only songs they have authored, i.e., do not perform any songs they have not authored.