One of the definitions of elementary topos in nLab says that a category is a topos if it has finite limits, it is cartesian closed and it has a subobject classifier.
However, Lawvere in the introduction to "Toposes, algebraic geometry and logic" says that a category is a topos if it is cartesian closed and it has a subobject classifier.
I think that perhaps you can derive finite limits from being cartesian closed and the subobject classifier. Is this the case? Where can I find such proof? Why nLab is making such assumption explicitely?