The many Buddhist references in the Persian literature of the period also provide evidence of Islamic–Buddhist cultural contact. Persian poetry, for example, often used the simile for palaces that they were "as beautiful as a Nowbahar (Nava Vihāra)."[citation needed] Further, at Nava Vihāra and Bamiyan, Buddha images, particularly of Maitreya, the future Buddha, had 'moon discs' or halo iconographically represented behind or around their heads.[citation needed] This led to the poetic depiction of pure beauty as someone having "the moon-shaped face of a Buddha." Thus, 11th-century Persian poems, such as Varqe and Golshah by Ayyuqi, use the word budh with a positive connotation for "Buddha," not with its second, derogatory meaning as "idol."[citation needed] It implies the ideal of asexual beauty in both men and women.[citation needed] Such references indicate that either Buddhist monasteries and images were present in these Iranian cultural areas at least through the early Mongol period in the 13th century or, at minimum, that a strong Buddhist legacy remained for centuries among the Buddhist converts to Islam.[citation needed]