Simplify the following text for a Grade 6 native English-speaking person.
Original: The Tibetan representatives who signed this document were Agvan Dorjiev , a Buryat , i.e. citizen of Russia , Chijamts , and Gendun-Galsan a Tibetan citizen .
Simplified: Those who signed for Tibet were Agvan Dorjiev , Chijamts , and Gendun-Galsan , who lived in Tibet . Dorijev was a Buryat , a citizen of Russia .