The Tibetan name for their land, Bod བོད་, means "Tibet" or "Tibetan Plateau", although it originally meant the central region around Lhasa, now known in Tibetan as Ü. The Standard Tibetan pronunciation of Bod, [pʰøʔ˨˧˨], is transcribed Bhö in Tournadre Phonetic Transcription, Bö in the THL Simplified Phonetic Transcription and Poi in Tibetan pinyin. Some scholars believe the first written reference to Bod "Tibet" was the ancient Bautai people recorded in the Egyptian Greek works Periplus of the Erythraean Sea (1st century CE) and Geographia (Ptolemy, 2nd century CE), itself from the Sanskrit form Bhauṭṭa of the Indian geographical tradition.