SoTransform(3) on Linux
The text 245831a730f9, as Debian 6.0 (Squeeze) shipped it.
The SoTransform class is the 'all-purpose' transformation node type. Like SoMatrixTransform, nodes of this type gives the application programmer maximum flexibility when specifying geometry transformations in a scene graph. If you want to set and keep the various components of the transformation matrix in separate entities, this node type is preferable, though.