The sacrifices of the pyrethes which Strabo observed in Cappadocia recall all the peculiarities of the avestan liturgy.
"The Oriental Religions in Roman Paganism"
Franz Cumont
The avestan religion was a reformation due to the genius of Zoroaster and therefore comparable with Buddhism rather than Hinduism, but the less systematic polytheism which preceded it contained much which reminds us of the Vedic hymns.
"Hinduism and Buddhism, Vol I. (of 3) An Historical Sketch"
Charles Eliot
344, an avestan subject is treated, the later Parsi doctrine of zrvan akarana.
"The Influence of India and Persia on the Poetry of Germany"
Arthur F. J. Remy