Question: What is the name of a district of Buenos Aires, Argentina and the southernmost barrio in Capital Federal, and contains the Autódromo Juan y Oscar Gálvez, home of the Argentine Grand Prix, a round of the Formula One championship?

Context paragraphs:
Argentine motorcycle Grand Prix: The Argentine motorcycle Grand Prix is the Argentine round of the FIM Grand Prix motorcycle racing championship.  The Grand Prix returned in 2014 with a race at Autódromo Termas de Río Hondo.  Previously, the event was held ten times at the Autódromo Oscar Alfredo Gálvez in the capital city of Buenos Aires between 1961 and 1999.

1980 Argentine Grand Prix: The 1980 Argentine Grand Prix was a Formula One motor race held on 13 January 1980 at the Autodromo Municipal Ciudad de Buenos Aires in Argentina.  It was the opening round of the 1980 Formula One season.  The race was the 16th Argentine Grand Prix.  It was the sixth to be held on the #15 variation of this racing facility in Buenos Aires.  The race was held over 53 laps of the 5.81-kilometre circuit for a total race distance of 308 kilometres.

Villa Riachuelo: Villa Riachuelo is a "barrio" (district) of Buenos Aires, Argentina.  It is the southernmost barrio in Capital Federal, and contains the Autódromo Juan y Oscar Gálvez, home of the Argentine Grand Prix until 1998.

Autódromo Juan y Oscar Gálvez: The Autódromo de Buenos Aires Juan y Oscar Gálvez (official name) is a 45,000 capacity motor racing circuit in Buenos Aires, Argentina built in 1952 under president Juan Perón, named "Autódromo 17 de Octubre" after the date of Loyalty Day until Perón's overthrow.  It was later renamed after Argentinian racing driver brothers, Juan Gálvez and Oscar Alfredo Gálvez.

1998 Argentine Grand Prix: The 1998 Argentine Grand Prix (formally the XXI Gran Premio Marlboro Argentina) was a Formula One motor race held at Autódromo Oscar Alfredo Gálvez, Buenos Aires, on 12 April 1998.  The race is (to date) the last Argentine Grand Prix.  It was the third race of the 1998 Formula One season.  The 72-lap race was won by Michael Schumacher for the Ferrari team, from a second position start.  Mika Häkkinen finished second in a McLaren, with Eddie Irvine third in the other Ferrari car.

1995 Argentine Grand Prix: The 1995 Argentine Grand Prix (formally the XVIII Gran Premio Marlboro de la Republica Argentina) was a Formula One motor race held on 9 April 1995 at the Autódromo Oscar Alfredo Gálvez, Buenos Aires, Argentina.  It was the second round of the 1995 Formula One season and was the first Formula One race to take place in Argentina since .  The 72-lap race was won by Damon Hill for the Williams team after starting from second position.  Jean Alesi finished second in a Ferrari, with Michael Schumacher third in a Benetton car.  David Coulthard, who started the race from pole position, spun out of the race on lap 16 with an electrical problem.

1997 Argentine Grand Prix: The 1997 Argentine Grand Prix was a Formula One motor race held at Autódromo Oscar Alfredo Gálvez in Buenos Aires, Argentina on 13 April 1997.  It was the third race of the 1997 Formula One season and the 600th World Championship event.  The 72-lap race was won by Williams driver Jacques Villeneuve after he started from pole position.  Eddie Irvine finished second for the Ferrari team and Jordan driver Ralf Schumacher came in third.

List of Autodromo de Buenos Aires fatalities: Fatal accidents to competitors at the Autódromo Juan y Oscar Gálvez, in Buenos Aires, Argentina during the 1000 km Buenos Aires and other national and international motor-sport events.

Argentine Grand Prix: The Argentine Grand Prix (Spanish: "Gran Premio de Argentina") was a round of the Formula One championship, held intermittently from to , all at the same autodrome in the Argentine national capital of Buenos Aires.  Argentine president Juan Perón was the driving force behind the creation of the circuit, after seeing the success of the country's own Juan Manuel Fangio.

1953 Argentine Grand Prix: The 1953 Argentine Grand Prix was race 1 of 9 in the 1953 World Championship of Drivers, which was run to Formula Two regulations in 1952 and 1953.  The race was held in Buenos Aires on January 18, 1953, at the Autódromo Galvez (official name: Autódromo Juan y Óscar Gálvez, also known as the Autódromo 17 de Octubre) as the first official Formula One race in South America.  Previously, the Indianapolis 500 (part of the Formula One championship calendar from 1950 to 1960) was the only Formula One championship race held outside of Europe but run to AAA regulations.

Supporting paragraphs: Villa Riachuelo Argentine Grand Prix
Answer: Villa Riachuelo