Published in Spring 1987 Zeiss Historica Journal
Author: Larry Gubas
See Page 3.
The author extended the list of possible suffixes within the Catalog or Bestellnummern numbers to identify additional film formats for the Ica and Zeiss Ikon cameras to /32 and listed the existence of plate film packs and roll film codes.
To go to the Journal itself, click on the year 1987 in the first line above.