The Rudolf Abel reference article from the English Wikipedia on 24-Apr-2004
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Rudolf Abel

Helping orphans the way you would do it
Rudolf Abel is best known as an alias used by Soviet spy Vilyam ("Willie") Genrikovich Fisher who from November, 1948 until his capture in June, 1957 was an undercover spy operating in New York City.

It was also the real name of another, less well known NKVD agent, who had once shared a flat with Fischer. The real Abel was born in Latvia in 1900 and died in 1955. Not much seems to be publicly known about his career. By adopting that alias on his arrest Fisher was able to signal his capture to the Soviet Government.