I'm currently writing up a project on Congruences, Units and Exponents of congruence classes and such like... I have found a quote on wikipedia which references a book called Contemporary abstract algebra by Joseph Gallian. The quote is

'If

*n* is finite, then there are exactly φ(n) elements that generate the group on their own, where φ is the

Euler phi function'

Now I can prove this if need be but we are supposed to reference things and Wikipedia is not referenceable. I was wonderring if anyone could confirm whether the quote is in the book or correct me on it. The book isnt in our university library and the similiar books that were dont seem that good IMO