Issue 75 of the German magazine Problem Forum (study section) September 2018.
Also you may find below the article: Stephen Rothwell - Wege zu Schachstudien - Anmerkungen und Gedanken.
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Open the 75 PDF here separately.
Open the Rothwell article here separately.
Stephen Rothwell-Tiefe-und-Schonheit-Die Studien von Richard Reti :