This high quality circuit with complementary symmetry was found in an Electronics World of 1966. It can be made with modern transistors like the BD or TIP series.
Using the Texas Instruments SN75489P this circuit was found in June 1978 Radio Electronics...
We found this circuit, which should only be used with incandescent lamps. In the Motorola Linear...
Found in Electronics Now from the 1980s, this amplifier can also be seen in commercial amplifiers...