Editing in 3D - Autodesk AutoCAD 2013 Practical 3D Drafting and Design - page 180

We specify the first point of the second pair on the objects to be placed. If, instead of
specifying a point we press Enter , the command is equivalent to MOVE :
Specify second source point: Point
We specify the second point of the second pair on the target object. These two points
define the first rotation:
Specify second destination point: Point
We specify the first point of the third pair on the objects to be placed. If, instead of
specifying a point we press Enter , the command allows you to align only in 2D (one
translation and one rotation) and prompts if we want to scale the selected objects
based on the two pairs of points:
Specify third source point or <continue>: Point
We specify the second point of the third pair on the target object. The selected ob-
jects are moved and rotated, so both planes are aligned:
Specify third destination point: Point