@inproceedings{
    mrpods986,
    author = {Mannila, Heikki and R{\"a}ih{\"a}, K.-J.},
    booktitle = "Fifth ACM SIGACT-SIGMOD Symposium on Principles of Database Systems",
    year = "1986",
    pages = "217-223",
    title = "Test data for relational queries"
}