Using pieces of different leases to make my own - copyrights

[Summer Noyes]

I am formulating my first fixed term lease agreement. I am in California where there seem to be a lot of little laws. I bought NOLO "The California Landlord's Law Book", which comes with downloadable forms, including a fixed term lease. Most of it I like, but there are bits and pieces that I want to add from the other book I bought from BP, "The Book on Managing Rental Properties", which also has a downloadable lease. Can I do this? If so, how do I legally give credit to both of these authors and not infringe on any copyrights? I wanted to use the NOLO lease as my basis and that comes with their copyright/logo in the footer. I realize they both provide the leases to use, but I wasn't sure about altering them? In the end, I'm still having the lease reviewed by a legal service as far as the lease itself. If anyone has info on this I'd greatly appreciate it. I did reach out to BP customer service and I am waiting to hear back. Thanks again.