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(1878-1929) A Danish mathematician. Erlang thelanguage and unit were named after him.Interested in the theory of probability, in 1908 Erlangjoined the Copenhagen Telephone Company where he studied theproblem of waiting times for telephone calls.He worked out how to calculate the fraction of callerswho must wait due to all the lines of an exchange being inuse. His formula for loss and waiting time was published in1917. It is now known as the "Erlang formula" and is stillin use today.Biography(http://www-history.mcs.st-andrews.ac.uk/~history/Mathematicians/Erlang.html),Biography(http://pass.maths.org.uk/issue2/erlang/index.html).