Sacred Liturgy and Gathas/Hymns of Zarathushtra
(Book of Common Prayer) including Yashts (hymns to the sacred beings), Niyayeshes (litanies to the sun, Mithra, Water, Fire, and the Moon), Gahs (prayers for the five periods of the day), Afrinagans (ceremonies of blessing), and other prayers
Extensions to the Liturgy
Primarily purity laws, myths, and some medical texts
The original Avesta canon comprised twenty-two books, (liturgical, historical, medical, legal). Its existence into the 9th century CE is well documented. Since then much of the non-liturgical texts have been lost.
In addition to the Avesta, Zoroastrians have numerous scriptures from the Sassanian period which are written in a middle-Persian dialect called Pahlavi. Many are exegetical Commentaries (called Zand) which translate, summarize and explain the Avesta. The Pahlavi texts also preserve large summaries and Translations of lost Avestan texts. They are considered of lesser authority than the Avesta.
Free eBooks (Can Be Downloaded):Right - Travel In Spiritual Worlds A Complete Guide On Astral Travels
Stephen Mcnallen - What Is Asatru
Robert Leo Odom - Sunday Sacredness In Roman Paganism
The Troth - Heathen Gods And Rites Some Frequently Asked Questions