Rails-models.md

+## `Referential` model
+
+Methods instead of `has_many` associations??
+
+## Model associated with a `Referential`
+
+### `Referential` support
+
+Classes with an association to `Referential` must:
+
+* include the `ReferentialSupport` module
+* not have a `belongs_to :referential` association because each `Referential` is a separate Postgres schema
+
+```ruby
+```
+
+### Objectids
+
+Objectids are only used on models contained in a `Referential`. Here's an example:
+
+```ruby
+```
+
+## Model not associated with a `Referential`
+
+```ruby
+```
+
+## Decorator
+
+![Action links](images/action_links.png)