But with both names sounding as though they could be female. It may come down to one's default assumptions - if one's default mental image of a novelist is female (a reasonable position for a female novelist), there may not be enough in the name to flip one over to the other conclusion.

For what it's worth, the only person I know named 'Nicola' happens to be a six foot, bearded Italian, so one can also be deceived by foreign usage.