Thank you very much x for correcting me. I misunderstood that that article is from Elektor.
The correct Elektor article(s) should be ...
Digital Benchtop Power Supply (1) Nov. 2001 - page 12
Digital Benchtop Power Supply (2) Dec. 2001 - page 98
Digital Benchtop Power Supply (3) Jan. 2002 - page 32