APA (7th ed.) Citation

Pitts, A. M. (1989). Non-trivial power types can't be subtypes of polymorphic types.

Chicago Style (17th ed.) Citation

Pitts, Andrew M. Non-trivial Power Types Can't Be Subtypes of Polymorphic Types. Cambridge, 1989.

MLA (9th ed.) Citation

Pitts, Andrew M. Non-trivial Power Types Can't Be Subtypes of Polymorphic Types. 1989.

Warning: These citations may not always be 100% accurate.