Kautilya's Arthashastra 2.35.12

2.35.12

parabhūmijātānāṃ vāristhalapathopayātānāṃ sāraphalgupuṇyānāṃ karmasu ca śulkavartanyātivāhikagulmataradeyabhāgabhakta.paṇyāgārapramāṇaṃ vidyuḥ //

As regards foreign merchandise of superior or inferior quality arriving thither by land or by water, they shall ascertain the amount of toll, road-cess, conveyance-cess, military cess, ferry-fare, and one-sixth portion (paid or payable by the merchants), the charges incurred by them for their own subsistence, and for the accommodation of their merchandise in warehouse (panyágára).