The Darlington configuration was invented by Sydney Darlington in 1953. Which used tow NPN or PNP pair to boost up the Beta of the Discrete Transistor .
In contrast to the Darlington arrangement, the Sziklai pair one NPN & one PNP Transistor, and so it is sometimes called the "complementary Darlington". Current gain is similar to that of a Darlington pair, which is the product of the gains of the two transistors. The configuration is named for its inventor George C. Sziklai. It was pateneted on September 11, 1956; U.S. Patent 2791644 .
Other references are :

U.S. Patent 2,762,870 Push-pull complementary type transistor amplifier. G.C.Sziklai, September 11, 1956
U.S. Patent 2,791,644 Push-pull amplifier with complementary type transistors. G.C.Sziklai, May 7, 1957

RCG Jan 2, 2010