Kitab al-Aghani, or the The Book of Songs, by Ali al-Isfahani (897-967) is a collection of Arabic songs and poems that were popular during tenth century, about 300 years after the birth of Islam. The 24-volume book begins with a collection of 100 songs which were ordered by the Caliph Harun al-Rashid, followed by other selected songs, especially those of the caliphs and their descendants. With every song, the author provides the text, the air according to traditional musical terminology, and detailed accounts concerning the poets who wrote the songs, often discussing composers and singers of both sexes. According to Brockelmann, “this book is our most important authority not only for literary history till into the third century of [Islam], but also for the history of civilization.” The collection was printed first in Bulaq, Egypt, in 1868. A second edition appeared in Cairo in 21 volumes in 1905-1906. An Index was published by Guidi in Leiden in 1895-1900. The Gorgias edtion, in 25 volumes, is based on a Cairo revision carried out starting in 1927 by a team of experts, and includes I. Guidi's indices.