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 | 1991 | |
|---|---|---|
| 2 |      | Stephen Ferg: Cardinality Constraints in Entity-Relationship Modeling. ER 1991: 1-30 |
| 1985 | ||
| 1 | | Stephen Ferg: Modelling the Time Dimension in an Entity-Relationship Diagram. ER 1985: 280-286 |