Are hyphens used correctly in the examples below? In other words, is there a rule in English that either requires or allows these hyphenations.
In my area of research, there is what is called the completely decomposed finite topology. Most sources write "the cdf-topology" to refer to this topology. Is this a correct hyphenation? Would it be correct to write "the cdf topology"?
Some source writes "the cdf-, finite and cdp-topologies", where cdp is an abbreviation for completely decomposed proper. Whereas, others write "the cdf, finite and cdp-topologies" or "the cdf, the finite and the cdp-topologies". Which one is correct, if any?
Some sources write "a 𝜏-cover", where 𝜏 is the Greek letter tau, used to refer to the topology the author is considering. However, all sources I have seen write "a Zariski cover", where the Zariski topology is named after the mathematician Oscar Zariski. Even when some mathematicians start with "let 𝜏 be the Zariski topology", later they write "a 𝜏-cover". Again, is the hyphen used correctly? Would it be correct to write "a 𝜏 cover"?
I have to confess that while I am asking for a rule (not only an aesthetic opinion), I do not know what constitutes a rule in English. So, I would be helpful if you could elaborate why the answer follows a rule, and not only an opinion.