International road transport is reserved to companies controlled by Argentine citizens and incorporated in accordance with Argentine legislation and with real domicile in Argentina.
"THE UNDER SECRETARY OF TRANSPORTATION RESOLVES:
Article 1 - Make effective the implementation of the International Land Transport Agreement, registered as a Partial Scope Agreement within the framework of the Latin American Integration Association (ALADI), in accordance with the mechanisms of the Montevideo Treaty of 1980.
[...]
AGREEMENT ON INTERNATIONAL LAND TRANSPORTATION
CHAPTER II - International road transport
Article 22. -
1. The signatory countries will only grant original permits to companies incorporated in accordance with their own legislation and with real domicile in their territory. [...]
3. More than half of the capital stock and effective control of the company will be in the hands of natural or naturalized citizens of the signatory country that grants the original permit. [...]" (Under-secretariat for Transport Resolution No. 263/90 (1 February 1991) implementing the International Land Transport Agreement between Argentina, Bolivia, Brazil, Chile, Paraguay, Peru and Uruguay, Article 1 of the Resolution and Article 22 of the Agreement [google translation])
Under-secretariat for Transport Resolution No. 263/90 (1 February 1991) implementing the International Land Transport Agreement between Argentina, Bolivia, Brazil, Chile, Paraguay, Peru and Uruguay, Article 1 of the Resolution and Article 22 of the Agreement 
[<a href="http://servicios.infoleg.gob.ar/infolegInternet/verNorma.do?id=20787">Resolution</a>]