Question: The Shadow DN3 was designed by Tony Southgate who was formerly from which British Formula One motor racing team?

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Fittipaldi Automotive: Fittipaldi Automotive, sometimes called Copersucar after its first major sponsor, was the only Formula One motor racing team and constructor ever to be based in Brazil.  It was formed during 1974 by racing driver Wilson Fittipaldi and his younger brother, double world champion Emerson, with money from the Brazilian sugar and alcohol cooperative Copersucar.  In 1976 Emerson surprised the motor racing world by leaving the title-winning McLaren team to drive for the unsuccessful family outfit.  Future world champion Keke Rosberg took his first podium finish in Formula One with the team.

Shadow DN1: The Shadow DN1 was a Formula One car used by the Shadow team during the 1973 Formula One season and the early stages of the following season.  The car was the first Formula One car for Shadow, which had previously participated in the CanAm Sportscar Series.  It was designed by former BRM engineer Tony Southgate.  The DN1 was also driven by Graham Hill for his privateer team, Embassy Hill.

Tony Southgate: Tony Southgate (born 25 May 1940, Coventry, England) is a British engineer and former racing car designer.  He designed many successful cars, including Jaguar's Le Mans-winning XJR-9, and cars for almost every type of circuit racing.  He was responsible for the chassis design of Ford's RS200 Group B rally car.  Southgate was employed as chief designer or technical director for many Formula One teams for over twenty years.  These teams included BRM, Shadow and Arrows.  Southgate retired after producing the Audi R8C, which was a major influence in the Bentley Speed 8, which won Le Mans in 2003.  He continues to be a regular visitor to current and historic race meetings.

BRM P261: The BRM P261, also known as the BRM P61 Mark II, is a Formula One motor racing car, designed and built by the British Racing Motors team in Bourne, Lincolnshire, England.  The BRM P261 was introduced for the 1964 Formula One season, and its design was an evolution of Tony Rudd's one-off BRM P61 car of .  The P261 had a relatively long racing career; variants of the car were still being entered for Formula One World Championship Grands Prix as late as .  During the course of their front-line career BRM P261s won six World Championship races, in the hands of works drivers Graham Hill and Jackie Stewart, and finished second in both the Drivers' and Constructors' Championship standings in 1964 and .  Stewart, Hill and Richard Attwood also used works P261s to compete in the Tasman Series in 1966.  The BRMs dominated, with Stewart winning four, Hill two, and Attwood one of the 1966 Tasman Series' eight races.  Stewart also won the title.  The works-backed Reg Parnell Racing team returned in 1967 with Stewart and Attwood, where Stewart added another two wins to his tally.  In terms of races won and total Championship points scored, the P261 was the most successful car in BRM's history.

British Racing Motors: British Racing Motors (BRM) was a British Formula One motor racing team.  Founded in 1945 and based in the market town of Bourne in Lincolnshire, it participated from 1950 to 1977, competing in 197 grands prix and winning seventeen.  BRM won the constructors' title in 1962 when its driver Graham Hill became world champion.  In 1963, 1964, 1965 and 1971, BRM came second in the constructors' competition.

Shadow DN3: The Shadow DN3 was a Formula One car used by the Shadow team during the 1974 Formula One season.  It also appeared twice during the early stages of the 1975 Formula One season in an updated DN3B form.  Designed by former BRM engineer Tony Southgate, the best finish achieved in a DN3 was Jean-Pierre Jarier's third place at the Monaco Grand Prix.

Williams Grand Prix Engineering: Williams Grand Prix Engineering Limited, currently racing in Formula One as Williams Martini Racing, is a British Formula One motor racing team and constructor.  It was founded and is run by team owner Sir Frank Williams and automotive engineer Sir Patrick Head.  The team was formed in 1977 after Frank Williams's two earlier unsuccessful F1 operations: Frank Williams Racing Cars (1969 to 1975) and Wolf–Williams Racing (1976).  All of Williams F1 chassis are called "FW" then a number, the FW being the initials of team owner, Frank Williams.

Arrows FA1: The Arrows FA1 was a Formula One car used by the Arrows team during the 1978 Formula One season.  The car was the first ever for the Arrows Racing Team and was designed by Tony Southgate and Dave Wass.

BRM P153: The BRM P153 was a Formula One racing car designed by Tony Southgate for the British Racing Motors team, which raced in the , and 1972 Formula One seasons.  It was powered by a 3.0-litre V12 engine.  Its best result was victory at the 1970 Belgian Grand Prix, where Pedro Rodríguez beat the second-placed March of Chris Amon by just 1.1 seconds.  The model was first shown in BRM's traditional British racing green, but by the time it appeared on the race tracks it was in the colours of the team's sponsor, Yardley of London.

Brabham BT60: The Brabham BT60 was the final series of Formula One racing cars built for the Brabham Formula One motor racing team.  Designed by Sergio Rinland, they raced in the 1991 and 1992 Formula One World Championships.  The car brought to a close Brabham's 30 years of construction of purpose-built racing cars, which began with Jack Brabham and Ron Tauranac and the Brabham BT1 Formula Junior design in 1961.

Supporting paragraphs: Shadow DN3 British Racing Motors
Answer: British Racing Motors