They are mentioned in sources such as the Qur'an, old Arabian poetry, Assyrian annals (Tamudi), in a Greek temple inscription from the northwest Hejaz of 169 CE, in a 5th-century Byzantine source and in Old North Arabian graffiti within Tayma.
They are mentioned in the victory annals of the Neo-Assyrian King, Sargon II (8th century BCE), who defeated these people in a campaign in northern Arabia.