In Catharism, did they use as a guide any books of the Bible and if so, which?

Cathars are known for having been a community which did not believe good things about the Old Testament deity and were based in the Languedoc region of today's southern France around the 12th century. Given that most Christian denominations in existence base their beliefs partly in the Old Testament deity, I was wondering, did the Cathars use as a guide any books of the Bible and if so, which? Were those books different than the ones we know? Did they have additional gospels besides the canon used by most Christians today?