This high current regulator with low voltage drop was found in the datasheet of the used integrated circuit itself. The transistor accepts an equivalent and must be provided with a heat sink.
This circuit was found in a 1992 publication, using an operational amplifier not very common...
This 13.8 V transistorized power supply with a current capacity of 20 A has a protection system...
This amplifier with 6 or 9 V power supply was sold in Japan in the 1960s. Its power was fractional watt...