'त्रिपिटक' ग्रंथ निम्नलिखित में से किस धर्म से संबंधित पवित्र शास्त्र हैं?

In Ancient Indian Statecraft, Kautilya's 'Rajamandala' theory primarily deals with:

The First Buddhist Council was held at ______.

Which ancient Indian text contains references indicating that population counts or census-like records were maintained in ancient India?