Matz demonstrates hand positions for the cello in a photograph probably from the 1960s. Some of these photographs are labeled "Violoncelist i njegov instrumenat," or "The Cellist and His Instrument," apparently the name for a method book or article that Matz wrote.
Rudolf Matz Musical Score Collection, SC003.1. Martha Blakeney Hodges Special Collections and University Archives, The University of North Carolina at Greensboro, NC, USA.