@article{POPL-2020-HuL,
	author        = "Jason Z. S. Hu and Ondrej Lhoták",
	doi           = "10.1145/3371077",
	journal       = "{Proceedings of the ACM on Programming Languages}",
	number        = "POPL",
	pages         = "30",
	publisher     = "{ACM}",
	title         = "{Undecidability of d<:  and its decidable fragments}",
	volume        = 4,
	year          = 2020,
}