Do you want a longer nap for YOU or your baby?
Yes there is a lot to do when you have a baby, and especially if you have a baby and other children or are trying to work as well. BUT your desire to have more free time when your baby is asleep is not going to be enough to convince your baby to sleep for longer!
So it can be a good idea to first work out why you want your baby to sleep for longer - is it because she is tired and grumpy, or is it because you feel you need her to sleep for longer as you need the time.
Trust me I spent a lot of time trying to get my toddlers to keep having a day sleep as I had work to do (like writing website articles!) but ultimately it was wasted time and stress that would have been better spent playing and enjoying my very strong willed, not sleeping 2 year old.