In computer science we discuss an abstract machine called a "deterministic finite automaton". The standard initialism for this term is "DFA". This makes sense in the singular usage of the initialism.
However, the pluralization of the word "automaton" is "automata". One speaks of "an automaton" or "many automata". Consequently, it seems intuitive to form an initialism of the phrase "deterministic finite automata" as "DFA".
This does not seem correct, as "DFA" could be either plural or singular. On the other hand, "DFAs" also does not seem correct because it would seem to expand to "deterministic finite automatons", a phrase which no self-respecting computer scientist would ever utter.
This appears to be a duplicate of the question here http://english.stackexchange.com/questions/322797/what-is-the-plural-of-the-abbreviation-of-multiplicity-automaton-ma-or-mas?newreg=f0092d85cdf4474186eea023c948f002What is the plural of the abbreviation of "multiplicity automaton", "MA" or "MAs"?
But that question was never clearly resolved. What to do?