" Pg.162 " Mahabodhi Vihar refers to the main Buddhist temple at Bodhgaya (Uruvela) at the spot where Gautam Buddha attained enlightenment. The Vihar includes the famous Bodhi tree (Ficus Religiosa or the peepal Tree) and the Vajrasana (Diamond throne). The original temple existed as tree shrine (bodhi-ghar) with railings constructed by Emperor Ashoka in 3rd century BCE. Its earliest depiction is found on reliefs at Bharahut (c. 80 BCE) and Sanchi (c. 25 BCE) stupas."
Pg.154 " Emperor Ashoka built a red sandstone structure with railings here in the 3rd century BCE to mark the exact spot of the meditation seat."India China Encyclopedia Vol 1. पृ॰ 154 & 162.
The two foreign inscription discovered at Buddhagayā mentioned Ashoka. Eleventh century Chinese monk Yun-shu inscription and a Burmese inscription categorically state that Asoka was the builder of the Buddhagaya temple . Cunningham's view, based on Hiuen-tsang's description, that the earlier sand-stone enclosure of the Bodhi Tree at Buddhagayā was a railing erected originally by Aśoka. Aśoka's association with Buddhagaya epigraphically connected by his Rock Edict VIII. According to the translation of H.A. Giles, the Chinese inscription contains a reference to king Aśhoka who is building the sambhogakāya of the Buddha , possibly indicating the present Buddhagaya temple itself. The Burmese inscription on the other hand clearly reckons the Buddhagaya temple as one of the 84,000 shrines said to have been erected by king Dharmāśoka, the ruler of Jambudvipa, two hundred and eighteen years after the nirvana of the Buddha."
Journal of Ancient Indian History, Vol-3. 1969–70. पृ॰ 91-93.सीएस1 रखरखाव: तिथि प्रारूप (link)