First time was around 1978 or 1979 summer, (i was around 10 years) around 8:00 hs. aprox. in Cordoba city, i was playing football in a street with many friends, the thing was seen by much of the city people, reported also in the local TV news and newspaper. It was a big smoke ring, donut shaped thing in the sky with one direction S.N. didnt seems to be inteligent flight, was seen also in another cities around.-In the third week of 1990, vacationing in the Lolog lake, near San Martin de los Andes, Patagonia, Argentina, i was with another 4 friends camping in the shore, (speaking with friend around a fire) of the lake and during the night (aprox. 22 or 23 hs.) saw the same white smokelike ring, donutlke shapped but was not made by cloud or smoke, if not like to be fluorescent but semi transparent (possible to see some stars behind the thing), it was near and we all saw for 20 minutes aproximately the huge thing, traveling slowly and rarely the thing started to disappear in a "dark hole in the sky".- I have never forgot the experience, after more then 20 years is present in my mind and during dreams sometimes.- I often see one of the another guy that also saw the thing.- This time was heaviest experience.- After notice the objet we told to some friends but didnt care about.- It was a very dark night without moon, and one of the friends saw first the objet and told "look what a beautifull it come the moon", i replied "is not the moon", everybody there were amused and firtsly scared, not after some minutes the object was in the sky. After 20 minutes aproximately the object disapear rarely in a black holelike in the middle of the sky.- Was very strange. The one of the friend was from Pergamino city in Buenos Aires province, he had taken many pictures with a Nikon cammera, starting to take pictures first with flash, lather without flash but without tripode and another with tripode, during the year after the experience i phoned him but didnt wanted to talk with me, strangely, rarely i dont know to now why.- I dont have pictures about the object unfortunately cannot help with documented evidences. - But the first object in 1978/79 was reported in local TV news and also La Voz del Interior newspaper. Was seen by all the city.- Congratulations for your work, best regards. G