From http://www.w3schools.com (Copyright Refsnes Data)
The reference-orientation property defines the direction for top for the content-rectangle of the reference-area.
| Value | Description |
|---|---|
| 0 | Default. The orientation of this area has the same orientation as the containing reference-area |
| 90 | The orientation is rotated 90 degrees from the orientation of the containing reference-area |
| 180 | The orientation is rotated 180 degrees from the orientation of the containing reference-area |
| 270 | The orientation is rotated 270 degrees from the orientation of the containing reference-area |
| -90 | Same as specifying 270 |
| -180 | Same as specifying 180 |
| -270 | Same as specifying 90 |
From http://www.w3schools.com (Copyright Refsnes Data)