Manasara 7.40

7.40

madhye cāṣṭakasaṃyuktaṃ sūtra maṇḍūkanāmakam
caturdikṣu catuḥsūtraṃ ṣoḍaśānyatra sūtrakam

joined with eight lines in the center, it is called the Maṇḍūka.
There are four lines in the four directions, and sixteen lines elsewhere;