In reply to Bruno Winck.

Thanks for these points of reference as well as your personal experience Bruno, particularly since I've not been able to find translations in English.

I've now got some clear evidence of the specific method going back to Konrad Gessner including the quirky use of numbering/alphabet that Luhmann uses which probably not coincidentally coincides with street address systems used in early Vienna.

In 1986 in the sixth grade I was taught to use index cards to do some research to write a paper, but nothing coming close to use as an actual thought out system. It's interesting to see how much of these taught practices had disappeared in just a few generations. And it seems all the worse that we're now trying to recreate them digitally without any hindsight of our shared history.

Thanks again!