@InProceedings{odersky:updates,
  author = 	"Martin Odersky",
  title = 	"How to Make Destructive Updates Less Destructive",
  pages = 	"25--26",
  booktitle = 	"Proc. 18th {ACM}
		 Symposium on Principles of Programming Languages",
  year = 	1991,
  month = 	"January"
}