@inproceedings{LICS-1989-Pitts,
	author        = "Andrew M. Pitts",
	booktitle     = "{Proceedings of the Fourth Annual Symposium on Logic in Computer Science}",
	doi           = "10.1109/LICS.1989.39154",
	isbn          = "0-8186-1954-6",
	pages         = "6--13",
	publisher     = "{IEEE Computer Society}",
	title         = "{Non-trivial Power Types Can’t Be Subtypes of Polymorphic Types}",
	year          = 1989,
}