In the head of Andromeda, there is a star of the second magnitude called Alpheratz and is one of those which form the square of Pegasus[…]. Alpheratz is on an imaginary line drawn from the north-easternmost star in the square of the Great Bear, through the north polar star, and distant from the latter about 61 degrees.
Source: wiktionary
[Alpheratz, Alpherat, and Sirrah are from the Arabians' Al Surrat al Faras, the Horse's Navel, as this star formerly was associated with Pegasus, whence it was transferred to the Woman's hair; and some one has strangely called it Umbilicus Andromedae. But in all late Arabian astronomy taken from Ptolemy it was described as Al Rās al Mar'ah al Musalsalah, the Head of the Woman in Chains.]
Source: wiktionary