In Ezeiza, after you pass customs, a sliding door opens, and you will see counters to your left and right, where a variety of services is offered.
One of this is Tienda León http://www.tiendaleon.com.ar/home/home.asp ; you may hire your taxi there. It costs about 180 pesos argentinos (aprox. 45 US$, or 36 euros). You must pay in advance, cash (in pesos argentinos, but you can ask if they accept other currency) or simply with credit card.
There are other companies, also without a desk. For instance, Omega Transfer http://www.omegatransfers.com.ar/ is one of them. In this company, transfers must be coordinated in advance: write an email to reservas@omegatransfers.com.ar indicating your name and flight number and also saying that you are going to the Math Congress at UBA. Then a driver with a poster with your name will pick you up at the airport. The trip is about 120 pesos (+ tip for the driver). You must pay cash with pesos argentinos or US dollars.
Bus number 107 stops at the corner of Blanco Encalada st. with Cabildo Ave. Tickets cost around 1.25 pesos which must be deposited in the ticketing machine, wich ONLY accepts coins.
The trip takes about 20 minutes and the School stop is the first after you cross Illia highway (the only highway in the trip). Get off the bus right after it enters the University campus. Lectures are in "Pabellón I".
If you look for a restaurant guide, Guia Oleo http://www.guiaoleo.com.ar/ is quite complete, you can do searchs by zones (e.g. "Belgrano", where Hotels Sarum and Sures are located).
Note that some web addresses can't be reached from the University network (they are blocked); Guia Oleo is one of those addresses. However you should have no difficulty reaching their page from the hotel or any other public location outside the University network.
The meeting point is IGLESIA DEL PILAR, 3 PM.
This is a colonial church (one of the oldest in Buenos Aires) just by the side of (the main entrence of) Recoleta's Cemetry.
One can get there by bus 60, from Cabildo Avenue (running in the same direction as when you go to take the bus to the School). You have to get aout of the bus at (Avenida) "Pueyrredon y las Heras" (pou ai RRR eh don y las eh ras), about 20 or 30 minutes trip.
If you take the subway, line D from Congreso de tucuman, until "Pueyrredon". Then walk through Pueyrredon avenue until Las Heras avenue (10 blocks aprox.).
If you continue walking on Pueyrredon avenue (going down), the first street after Las Heras avenue, turn to your right. After a minute you will see a long wall: that's the back part of the cemetry. If you imagine the cemetry as a disk, walk arount its boundary anti-clockwise (looking the disk from the sky!). You will find the main entrance, and after that, the church.
In case you are lost, ask for Recoleta's Cemetry.
http://www.bue.gov.ar/actividades/index.php?lang=en
In particular go to: ---> CULTURA ---> BARES NOTABLES
Ver Santalo Cimpa-School Map en un mapa
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