@inproceedings{STOC-1970-Burkhard,
	author        = "Walter A. Burkhard",
	booktitle     = "{Proceedings of the Second Annual ACM Symposium on Theory of Computing}",
	doi           = "10.1145/800161.805150",
	pages         = "62--69",
	publisher     = "{ACM}",
	title         = "{Complexity Problems in Real Time Computation}",
	year          = 1970,
}