@inproceedings{POPL-1990-GraverJ,
	author        = "Justin O. Graver and Ralph E. Johnson",
	booktitle     = "{Conference Record of the 17th Annual Symposium on Principles of Programming Languages}",
	doi           = "10.1145/96709.96722",
	editor        = "Frances E. Allen",
	isbn          = "0-89791-343-4",
	pages         = "136--150",
	publisher     = "{ACM Press}",
	title         = "{A Type System for Smalltalk}",
	year          = 1990,
}