Auction # 2434 ARGENTINA: Special September auction

2 Airmail covers sent from Buenos Aires to Switzerland on 12/MAY/1930 and 23/AU/1930 by C.G.A. The former franked with 12c. (regular rate) + 1.80P. (airmail fee) + 2c.(to pay the additional fee that the C.G.A. charged for a few weeks for letters that continued to Switzerland by airmail). The other letter franked with 12c. + 1.74c. for airmail fee, showing that at that moment there was NO additional fee of 2c. for letters to Switzerland by airmail. Both covers bear on back arrival marks of Paris, in both cases they arrived on the same day they were dispatched, excellent quality, rare lot!