[CGM-to-HTML] The viewer shall load the document into the full, original window (thus canceling all other frames). This value is equivalent to _self if the current frame has no parent. [CGM-to-CGM] The viewer shall load the picture into the full, original window (thus canceling all other frames). This value is equivalent to _self if the current frame has no parent. [Behavior] 
_top
_ b l a n k
_ s e l f
_ p a r e n t
_ r e p l a c e
_ t o p
T a r g e t