 Our enumeration algorithm can be extended to other Steiner problems : minimal Steiner forests, minimal terminal Steiner trees,  minimal directed Steiner trees.
<fluency>  Our enumeration algorithm can be extended to other Steiner problems : minimal Steiner forests, minimal terminal Steiner trees,  minimal directed Steiner trees.
 Our enumeration algorithm can be extended to other Steiner problems : minimal Steiner forests, minimal terminal Steiner trees, and minimal directed Steiner trees.