recursion.

AS I understand, there must be a stopping condition in recursive
functions.

suppose my function is like this -

void build_kdtree(kdnode *kd, int axis, int depth)
{

if(kd->maxspheres <= MINSPHERES || depth >= DEPTHLIMIT)
{
kd->left = kd->right = NULL;

}

else
{

,,,,,,,,

build_kdtree(kd->left, axis, depth+1);
build_kdtree(kd->right, axis, depth+1);

}

My question is -

1. Is the stopping condition in if sufficient or some return value is
also necessary
2. Is this a right way to build a recursive function ?
.