What are the compounds that this article refers to?

The linked article studies the effects of a set of organophosphorus compounds on the bioelectrical activity in the digestive system. The OP compounds studied are referred to in the abstract as IMFF, PMFF, and MEDETFK. Some OP antidote referred to as N-5 (T) is also studied. Now, the original article is in Bulgarian, and only the abstract is available on the internet in English. Based on the fact that the English translation of the abstract refers to organophosphorus compounds with the abbreviation FOV, I would guess that the abbreviations IMFF, PMFF, and MEDETFK are transliterated from Bulgarian as-is. I would also guess that IMFF and PMFF refer to sarin and soman respectively. My question is: What compound does the abbreviation MEDETFK refer to, and what is the OP antidote N-5 (T)?


The article in question: <https://pubmed.ncbi.nlm.nih.gov/4806515/>


Update: I have managed to procure the full article. It does not elaborate on what compounds it refers to. Here is the article: <https://i.stack.imgur.com/oBvVX.jpg>


