• Louis H. Kauffman if you're mostly interested in the pure math aspect of it. He wrote numerous papers on the topic of von Förster's paper, you can find one them here: https://arxiv.org/abs/1109.1892
• JM Stern and CAB Pereira if you're mostly interested in the application to statistics and fundamental questions of the epistemology of statistics. I wrote a thread on their works on my Twitter account at some point: https://twitter.com/no_identd/status/877883663014400000
Try this AMAZING paper by AF Zimpel: http://www.emeraldinsight.com/doi/pdf/10.1108/03684920510581...
Also, this paper by Heinz von Förster (first order author) and Karl H. Miiller (second order editor), where Miller basically took a lot of old papers by von Förster and rearranged them to give a more coherent view for certain types of readers:
http://www.univie.ac.at/constructivism/archive/fulltexts/309...
Did you read & comprehend the two papers linked before trying to make sense of it?
If so, mind sharing your notes? Pretty sure you must have taken some if you claim to have comprehended them.
Anyone who wishes to explore this idea would do well to go back to the basics of neural nets and read Warren McCulloch's seminal papers on neural nets, from the 40s:
http://www.cse.chalmers.se/~coquand/AUTOMATA/mcp.pdf A Logical Calculus of the ideas immanent in nervous activity
http://vordenker.de/ggphilosophy/mcculloch_heterarchy.pdf A heterarchy of values determined by the topology of neural nets
(After having read those two papers, one can then try to make sense of Heinz von Förster's masterpiece, http://www.univie.ac.at/constructivism/archive/fulltexts/127..., Objects: Tokens for (Eigen-)Behaviors, which also bears some relevance to this matter. However, most people find it incomprehensible.)